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.TH DWM 1 dwm\-VERSION
.SH NAME
dwm \- dynamic window manager
.SH SYNOPSIS
.B dwm
.RB [ \-v ]
.SH DESCRIPTION
dwm is a dynamic window manager for X. It manages windows in tiled, monocle
and floating layouts. Either layout can be applied dynamically, optimising the
environment for the application in use and the task performed.
.P
In tiled layout windows are managed in a master and stacking area. The master
area contains the window which currently needs most attention, whereas the
stacking area contains all other windows. In monocle layout all windows are
maximised to the screen size. In floating layout windows can be resized and
moved freely. Dialog windows are always managed floating, regardless of the
layout applied.
.P
Windows are grouped by tags. Each window can be tagged with one or multiple
tags. Selecting certain tags displays all windows with these tags.
.P
dwm contains a small status bar which displays all available tags, the layout,
the title of the focused window, and the text read from standard input. A
floating window is indicated with an empty square and a maximised
floating window is indicated with a filled square before the windows
title.  The selected tags are indicated with a different color. The tags of
the focused window are indicated with a filled square in the top left
corner.  The tags which are applied to one or more windows are indicated
with an empty square in the top left corner.
.P
dwm draws a small border around windows to indicate the focus state.
.SH OPTIONS
.TP
.B \-v
prints version information to standard output, then exits.
.SH USAGE
.SS Status bar
.TP
.B Standard input
is read and displayed in the status text area.
.TP
.B Button1
click on a tag label to display all windows with that tag, click on the layout
label toggles between tiled and floating layout.
.TP
.B Button3
click on a tag label adds/removes all windows with that tag to/from the view.
.TP
.B Mod1\-Button1
click on a tag label applies that tag to the focused window.
.TP
.B Mod1\-Button3
click on a tag label adds/removes that tag to/from the focused window.
.SS Keyboard commands
.TP
.B Mod1\-Shift\-Return
Start
.BR xterm.
.TP
.B Mod1\-Return
Zooms/cycles current window to/from master area (tiled layout only).
.TP
.B Mod1\-Tab
Toggles to the previously selected tags.
.TP
.B Mod1\-f
Apply floating layout.
.TP
.B Mod1\-m
Apply monocle layout.
.TP
.B Mod1\-t
Apply tiled layout.
.TP
.B Mod1\-j
Focus next window.
.TP
.B Mod1\-k
Focus previous window.
.TP
.B Mod1\-r
Re-applies tagging rules to all windows.
.TP
.B Mod1\-Shift\-[1..n]
Apply
.RB nth
tag to current window.
.TP
.B Mod1\-Shift\-0
Apply all tags to current window.
.TP
.B Mod1\-Control\-Shift\-[1..n]
Add/remove
.B nth
tag to/from current window.
.TP
.B Mod1\-Shift\-c
Close focused window.
.TP
.B Mod1\-Shift\-space
Toggle focused window between tiled and floating state.
.TP
.B Mod1\-[1..n]
View all windows with
.BR nth
tag.
.TP
.B Mod1\-0
View all windows with any tag.
.TP
.B Mod1\-Control\-[1..n]
Add/remove all windows with
.BR nth
tag to/from the view.
.TP
.B Mod1\-Shift\-q
Quit dwm.
.SS Mouse commands
.TP
.B Mod1\-Button1
Move current window while dragging. Tiled windows will be toggled to the floating state.
.TP
.B Mod1\-Button2
Zooms/cycles current window to/from master area. If it is floating (but not fixed) it will be toggled to the tiled state instead.
.TP
.B Mod1\-Button3
Resize current window while dragging. Tiled windows will be toggled to the floating state.
.SH CUSTOMIZATION
dwm is customized by creating a custom config.h and (re)compiling the source
code. This keeps it fast, secure and simple.
.SH SEE ALSO
.BR dmenu (1)
.SH BUGS
The status bar may display
.BR "EOF"
when dwm has been started by an X session manager like
.BR xdm (1),
because those close standard output before executing dwm.
.P
Java applications which use the XToolkit/XAWT backend may draw grey windows
only. The XToolkit/XAWT backend breaks ICCCM-compliance in recent JDK 1.5 and early
JDK 1.6 versions, because it assumes a reparenting window manager. As a workaround
you can use JDK 1.4 (which doesn't contain the XToolkit/XAWT backend) or you
can set the following environment variable (to use the older Motif
backend instead):
.BR AWT_TOOLKIT=MToolkit .
.P
Recent GTK 2.10.9+ versions contain a broken
.BR Save\-As
file dialog implementation,
which requests to reconfigure its window size in an endless loop. However, its
window is still respondable during this state, so you can simply ignore the flicker
until a new GTK version appears, which will fix this bug, approximately
GTK 2.10.12+ versions.
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type global {
  name: (handle array byte)
  value: (handle cell)
}

type global-table {
  data: (handle array global)
  final-index: int
}

fn initialize-globals _self: (addr global-table) {
  var self/esi: (addr global-table) <- copy _self
  var data-ah/eax: (addr handle array global) <- get self, data
  populate data-ah, 0x40
  # generic
  append-primitive self, "="
  # for numbers
  append-primitive self, "+"
  append-primitive self, "-"
  append-primitive self, "*"
  append-primitive self, "/"
  append-primitive self, "sqrt"
  append-primitive self, "abs"
  append-primitive self, "sgn"
  append-primitive self, "<"
  append-primitive self, ">"
  append-primitive self, "<="
  append-primitive self, ">="
  # for pairs
  append-primitive self, "car"
  append-primitive self, "cdr"
  append-primitive self, "cons"
  # for screens
  append-primitive self, "print"
  append-primitive self, "clear"
  append-primitive self, "lines"
  append-primitive self, "columns"
  append-primitive self, "up"
  append-primitive self, "down"
  append-primitive self, "left"
  append-primitive self, "right"
  append-primitive self, "cr"
  append-primitive self, "pixel"
  append-primitive self, "width"
  append-primitive self, "height"
  # for keyboards
  append-primitive self, "key"
  # for streams
  append-primitive self, "stream"
  append-primitive self, "write"
  append-primitive self, "abort"
  # keep sync'd with render-primitives
}

fn load-globals in: (addr handle cell), self: (addr global-table) {
  var remaining-ah/esi: (addr handle cell) <- copy in
  {
    var _remaining/eax: (addr cell) <- lookup *remaining-ah
    var remaining/ecx: (addr cell) <- copy _remaining
    var done?/eax: boolean <- nil? remaining
    compare done?, 0/false
    break-if-!=
    var curr-ah/eax: (addr handle cell) <- get remaining, left
    var curr/eax: (addr cell) <- lookup *curr-ah
    remaining-ah <- get remaining, right
    var name-ah/ecx: (addr handle cell) <- get curr, left
    var value-ah/ebx: (addr handle cell) <- get curr, right
    var name/eax: (addr cell) <- lookup *name-ah
    var name-data-ah/eax: (addr handle stream byte) <- get name, text-data
    var name-data/eax: (addr stream byte) <- lookup *name-data-ah
    append-global-binding-of-stream self, name-data, *value-ah
    loop
  }
}

fn write-globals out: (addr stream byte), _self: (addr global-table) {
  var self/esi: (addr global-table) <- copy _self
  write out, "  (globals . (\n"
  var data-ah/eax: (addr handle array global) <- get self, data
  var data/eax: (addr array global) <- lookup *data-ah
  var final-index/edx: (addr int) <- get self, final-index
  var curr-index/ecx: int <- copy 1/skip-0
  {
    compare curr-index, *final-index
    break-if->
    var curr-offset/ebx: (offset global) <- compute-offset data, curr-index
    var curr/ebx: (addr global) <- index data, curr-offset
    var curr-value-ah/edx: (addr handle cell) <- get curr, value
    var curr-value/eax: (addr cell) <- lookup *curr-value-ah
    var curr-type/eax: (addr int) <- get curr-value, type
    {
      compare *curr-type, 4/primitive-function
      break-if-=
      compare *curr-type, 5/screen
      break-if-=
      compare *curr-type, 6/keyboard
      break-if-=
      compare *curr-type, 3/stream  # not implemented yet
      break-if-=
      write out, "    ("
      var curr-name-ah/eax: (addr handle array byte) <- get curr, name
      var curr-name/eax: (addr array byte) <- lookup *curr-name-ah
      write out, curr-name
      write out, " . "
      print-cell curr-value-ah, out, 0/no-trace
      write out, ")\n"
    }
    curr-index <- increment
    loop
  }
  write out, "  ))\n"
}

fn render-globals screen: (addr screen), _self: (addr global-table), xmin: int, ymin: int, xmax: int, ymax: int {
  clear-rect screen, xmin, ymin, xmax, ymax, 0x12/bg=almost-black
  var self/esi: (addr global-table) <- copy _self
  # render primitives
  render-primitives screen, xmin, ymin, xmax, ymax
  var data-ah/eax: (addr handle array global) <- get self, data
  var data/eax: (addr array global) <- lookup *data-ah
  var curr-index/edx: int <- copy 1
  {
    var curr-offset/ebx: (offset global) <- compute-offset data, curr-index
    var curr/ebx: (addr global) <- index data, curr-offset
    var continue?/eax: boolean <- primitive-global? curr
    compare continue?, 0/false
    break-if-=
    curr-index <- increment
    loop
  }
  var lowest-index/edi: int <- copy curr-index
  var y/ecx: int <- copy ymin
  var final-index/edx: (addr int) <- get self, final-index
  var curr-index/edx: int <- copy *final-index
  {
    compare curr-index, lowest-index
    break-if-<
    compare y, ymax
    break-if->=
    {
      var curr-offset/ebx: (offset global) <- compute-offset data, curr-index
      var curr/ebx: (addr global) <- index data, curr-offset
      var curr-name-ah/eax: (addr handle array byte) <- get curr, name
      var _curr-name/eax: (addr array byte) <- lookup *curr-name-ah
      var curr-name/edx: (addr array byte) <- copy _curr-name
      var x/eax: int <- copy xmin
      x, y <- draw-text-wrapping-right-then-down screen, curr-name, xmin, ymin, xmax, ymax, x, y, 0x2a/fg=orange, 0x12/bg=almost-black
      x, y <- draw-text-wrapping-right-then-down screen, " <- ", xmin, ymin, xmax, ymax, x, y, 7/fg=grey, 0x12/bg=almost-black
      var curr-value/edx: (addr handle cell) <- get curr, value
      var s-storage: (stream byte 0x400)
      var s/ebx: (addr stream byte) <- address s-storage
      print-cell curr-value, s, 0/no-trace
      x, y <- draw-stream-wrapping-right-then-down screen, s, xmin, ymin, xmax, ymax, x, y, 3/fg=cyan, 0x12/bg=almost-black
    }
    curr-index <- decrement
    y <- increment
    loop
  }
}

fn render-primitives screen: (addr screen), xmin: int, ymin: int, xmax: int, ymax: int {
  var y/ecx: int <- copy ymax
  y <- subtract 0xf
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "cursor graphics", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  print", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen a -> a", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  lines columns", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen -> number", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  up down left right", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  cr", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen   ", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, "# move cursor down and to left margin", tmpx, xmax, y, 9/fg=blue, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "pixel graphics", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  width height", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen -> number", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  pixel", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen x y color", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "screen/keyboard", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  clear", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": screen", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  key", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": () -> grapheme?", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "streams", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  stream", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": () -> stream ", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "  write", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, ": stream grapheme -> stream", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  y <- increment
  var tmpx/eax: int <- copy xmin
  tmpx <- draw-text-rightward screen, "numbers: ", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, "+ - * / sqrt abs sgn = < > <= >=   ", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, "pairs: ", tmpx, xmax, y, 7/fg=grey, 0x12/bg=almost-black
  tmpx <- draw-text-rightward screen, "car cdr cons", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
}

fn primitive-global? _x: (addr global) -> _/eax: boolean {
  var x/eax: (addr global) <- copy _x
  var value-ah/eax: (addr handle cell) <- get x, value
  var value/eax: (addr cell) <- lookup *value-ah
  compare value, 0/null
  {
    break-if-!=
    return 0/false
  }
  var value-type/eax: (addr int) <- get value, type
  compare *value-type, 4/primitive
  {
    break-if-=
    return 0/false
  }
  return 1/true
}

fn append-primitive _self: (addr global-table), name: (addr array byte) {
  var self/esi: (addr global-table) <- copy _self
  var final-index-addr/ecx: (addr int) <- get self, final-index
  increment *final-index-addr
  var curr-index/ecx: int <- copy *final-index-addr
  var data-ah/eax: (addr handle array global) <- get self, data
  var data/eax: (addr array global) <- lookup *data-ah
  var curr-offset/esi: (offset global) <- compute-offset data, curr-index
  var curr/esi: (addr global) <- index data, curr-offset
  var curr-name-ah/eax: (addr handle array byte) <- get curr, name
  copy-array-object name, curr-name-ah
  var curr-value-ah/eax: (addr handle cell) <- get curr, value
  new-primitive-function curr-value-ah, curr-index
}

fn append-global _self: (addr global-table), name: (addr array byte), value: (handle cell) {
  var self/esi: (addr global-table) <- copy _self
  var final-index-addr/ecx: (addr int) <- get self, final-index
  increment *final-index-addr
  var curr-index/ecx: int <- copy *final-index-addr
  var data-ah/eax: (addr handle array global) <- get self, data
  var data/eax: (addr array global) <- lookup *data-ah
  var curr-offset/esi: (offset global) <- compute-offset data, curr-index
  var curr/esi: (addr global) <- index data, curr-offset
  var curr-name-ah/eax: (addr handle array byte) <- get curr, name
  copy-array-object name, curr-name-ah
  var curr-value-ah/eax: (addr handle cell) <- get curr, value
  copy-handle value, curr-value-ah
}

fn append-global-binding-of-stream _self: (addr global-table), name: (addr stream byte), value: (handle cell) {
  var self/esi: (addr global-table) <- copy _self
  var final-index-addr/ecx: (addr int) <- get self, final-index
  increment *final-index-addr
  var curr-index/ecx: int <- copy *final-index-addr
  var data-ah/eax: (addr handle array global) <- get self, data
  var data/eax: (addr array global) <- lookup *data-ah
  var curr-offset/esi: (offset global) <- compute-offset data, curr-index
  var curr/esi: (addr global) <- index data, curr-offset
  var curr-name-ah/eax: (addr handle array byte) <- get curr, name
  rewind-stream name
  stream-to-array name, curr-name-ah
  var curr-value-ah/eax: (addr handle cell) <- get curr, value
  copy-handle value, curr-value-ah
}

fn lookup-symbol-in-globals _sym: (addr cell), out: (addr handle cell), _globals: (addr global-table), trace: (addr trace), screen-cell: (addr handle cell), keyboard-cell: (addr handle cell) {
  var sym/eax: (addr cell) <- copy _sym
  var sym-name-ah/eax: (addr handle stream byte) <- get sym, text-data
  var _sym-name/eax: (addr stream byte) <- lookup *sym-name-ah
  var sym-name/edx: (addr stream byte) <- copy _sym-name
  var globals/esi: (addr global-table) <- copy _globals
  {
    compare globals, 0
    break-if-=
    var curr-index/ecx: int <- find-symbol-in-globals globals, sym-name
    compare curr-index, -1/not-found
    break-if-=
    var global-data-ah/eax: (addr handle array global) <- get globals, data
    var global-data/eax: (addr array global) <- lookup *global-data-ah
    var curr-offset/ebx: (offset global) <- compute-offset global-data, curr-index
    var curr/ebx: (addr global) <- index global-data, curr-offset
    var curr-value/eax: (addr handle cell) <- get curr, value
    copy-object curr-value, out
    return
  }
  # if sym is "screen" and screen-cell exists, return it
  {
    var sym-is-screen?/eax: boolean <- stream-data-equal? sym-name, "screen"
    compare sym-is-screen?, 0/false
    break-if-=
    compare screen-cell, 0
    break-if-=
    copy-object screen-cell, out
    return
  }
  # if sym is "keyboard" and keyboard-cell exists, return it
  {
    var sym-is-keyboard?/eax: boolean <- stream-data-equal? sym-name, "keyboard"
    compare sym-is-keyboard?, 0/false
    break-if-=
    compare keyboard-cell, 0
    break-if-=
    copy-object keyboard-cell, out
    return
  }
  # otherwise error "unbound symbol: ", sym
  var stream-storage: (stream byte 0x40)
  var stream/ecx: (addr stream byte) <- address stream-storage
  write stream, "unbound symbol: "
  rewind-stream sym-name
  write-stream stream, sym-name
  trace trace, "error", stream
}

# return the index in globals containing 'sym'
# or -1 if not found
fn find-symbol-in-globals _globals: (addr global-table), sym-name: (addr stream byte) -> _/ecx: int {
  var globals/esi: (addr global-table) <- copy _globals
  compare globals, 0
  {
    break-if-!=
    return -1/not-found
  }
  var global-data-ah/eax: (addr handle array global) <- get globals, data
  var global-data/eax: (addr array global) <- lookup *global-data-ah
  var final-index/ecx: (addr int) <- get globals, final-index
  var curr-index/ecx: int <- copy *final-index
  {
    compare curr-index, 0
    break-if-<
    var curr-offset/ebx: (offset global) <- compute-offset global-data, curr-index
    var curr/ebx: (addr global) <- index global-data, curr-offset
    var curr-name-ah/eax: (addr handle array byte) <- get curr, name
    var curr-name/eax: (addr array byte) <- lookup *curr-name-ah
    var found?/eax: boolean <- stream-data-equal? sym-name, curr-name
    compare found?, 0/false
    {
      break-if-=
      return curr-index
    }
    curr-index <- decrement
    loop
  }
  return -1/not-found
}

# a little strange; goes from value to name and selects primitive based on name
fn apply-primitive _f: (addr cell), args-ah: (addr handle cell), out: (addr handle cell), _globals: (addr global-table), trace: (addr trace) {
  var f/esi: (addr cell) <- copy _f
  var f-index-a/ecx: (addr int) <- get f, index-data
  var f-index/ecx: int <- copy *f-index-a
  var globals/eax: (addr global-table) <- copy _globals
  var global-data-ah/eax: (addr handle array global) <- get globals, data
  var global-data/eax: (addr array global) <- lookup *global-data-ah
  var f-offset/ecx: (offset global) <- compute-offset global-data, f-index
  var f-value/ecx: (addr global) <- index global-data, f-offset
  var f-name-ah/ecx: (addr handle array byte) <- get f-value, name
  var f-name/eax: (addr array byte) <- lookup *f-name-ah
  {
    var is-add?/eax: boolean <- string-equal? f-name, "+"
    compare is-add?, 0/false
    break-if-=
    apply-add args-ah, out, trace
    return
  }
  {
    var is-subtract?/eax: boolean <- string-equal? f-name, "-"
    compare is-subtract?, 0/false
    break-if-=
    apply-subtract args-ah, out, trace
    return
  }
  {
    var is-multiply?/eax: boolean <- string-equal? f-name, "*"
    compare is-multiply?, 0/false
    break-if-=
    apply-multiply args-ah, out, trace
    return
  }
  {
    var is-divide?/eax: boolean <- string-equal? f-name, "/"
    compare is-divide?, 0/false
    break-if-=
    apply-divide args-ah, out, trace
    return
  }
  {
    var is-square-root?/eax: boolean <- string-equal? f-name, "sqrt"
    compare is-square-root?, 0/false
    break-if-=
    apply-square-root args-ah, out, trace
    return
  }
  {
    var is-abs?/eax: boolean <- string-equal? f-name, "abs"
    compare is-abs?, 0/false
    break-if-=
    apply-abs args-ah, out, trace
    return
  }
  {
    var is-sgn?/eax: boolean <- string-equal? f-name, "sgn"
    compare is-sgn?, 0/false
    break-if-=
    apply-sgn args-ah, out, trace
    return
  }
  {
    var is-car?/eax: boolean <- string-equal? f-name, "car"
    compare is-car?, 0/false
    break-if-=
    apply-car args-ah, out, trace
    return
  }
  {
    var is-cdr?/eax: boolean <- string-equal? f-name, "cdr"
    compare is-cdr?, 0/false
    break-if-=
    apply-cdr args-ah, out, trace
    return
  }
  {
    var is-cons?/eax: boolean <- string-equal? f-name, "cons"
    compare is-cons?, 0/false
    break-if-=
    apply-cons args-ah, out, trace
    return
  }
  {
    var is-structurally-equal?/eax: boolean <- string-equal? f-name, "="
    compare is-structurally-equal?, 0/false
    break-if-=
    apply-structurally-equal args-ah, out, trace
    return
  }
  {
    var is-lesser?/eax: boolean <- string-equal? f-name, "<"
    compare is-lesser?, 0/false
    break-if-=
    apply-< args-ah, out, trace
    return
  }
  {
    var is-greater?/eax: boolean <- string-equal? f-name, ">"
    compare is-greater?, 0/false
    break-if-=
    apply-> args-ah, out, trace
    return
  }
  {
    var is-lesser-or-equal?/eax: boolean <- string-equal? f-name, "<="
    compare is-lesser-or-equal?, 0/false
    break-if-=
    apply-<= args-ah, out, trace
    return
  }
  {
    var is-greater-or-equal?/eax: boolean <- string-equal? f-name, ">="
    compare is-greater-or-equal?, 0/false
    break-if-=
    apply->= args-ah, out, trace
    return
  }
  {
    var is-print?/eax: boolean <- string-equal? f-name, "print"
    compare is-print?, 0/false
    break-if-=
    apply-print args-ah, out, trace
    return
  }
  {
    var is-clear?/eax: boolean <- string-equal? f-name, "clear"
    compare is-clear?, 0/false
    break-if-=
    apply-clear args-ah, out, trace
    return
  }
  {
    var is-lines?/eax: boolean <- string-equal? f-name, "lines"
    compare is-lines?, 0/false
    break-if-=
    apply-lines args-ah, out, trace
    return
  }
  {
    var is-columns?/eax: boolean <- string-equal? f-name, "columns"
    compare is-columns?, 0/false
    break-if-=
    apply-columns args-ah, out, trace
    return
  }
  {
    var is-up?/eax: boolean <- string-equal? f-name, "up"
    compare is-up?, 0/false
    break-if-=
    apply-up args-ah, out, trace
    return
  }
  {
    var is-down?/eax: boolean <- string-equal? f-name, "down"
    compare is-down?, 0/false
    break-if-=
    apply-down args-ah, out, trace
    return
  }
  {
    var is-left?/eax: boolean <- string-equal? f-name, "left"
    compare is-left?, 0/false
    break-if-=
    apply-left args-ah, out, trace
    return
  }
  {
    var is-right?/eax: boolean <- string-equal? f-name, "right"
    compare is-right?, 0/false
    break-if-=
    apply-right args-ah, out, trace
    return
  }
  {
    var is-cr?/eax: boolean <- string-equal? f-name, "cr"
    compare is-cr?, 0/false
    break-if-=
    apply-cr args-ah, out, trace
    return
  }
  {
    var is-pixel?/eax: boolean <- string-equal? f-name, "pixel"
    compare is-pixel?, 0/false
    break-if-=
    apply-pixel args-ah, out, trace
    return
  }
  {
    var is-width?/eax: boolean <- string-equal? f-name, "width"
    compare is-width?, 0/false
    break-if-=
    apply-width args-ah, out, trace
    return
  }
  {
    var is-height?/eax: boolean <- string-equal? f-name, "height"
    compare is-height?, 0/false
    break-if-=
    apply-height args-ah, out, trace
    return
  }
  {
    var wait-for-key?/eax: boolean <- string-equal? f-name, "key"
    compare wait-for-key?, 0/false
    break-if-=
    apply-wait-for-key args-ah, out, trace
    return
  }
  {
    var is-stream?/eax: boolean <- string-equal? f-name, "stream"
    compare is-stream?, 0/false
    break-if-=
    apply-stream args-ah, out, trace
    return
  }
  {
    var write?/eax: boolean <- string-equal? f-name, "write"
    compare write?, 0/false
    break-if-=
    apply-write args-ah, out, trace
    return
  }
  {
    var abort?/eax: boolean <- string-equal? f-name, "abort"
    compare abort?, 0/false
    break-if-=
    apply-abort args-ah, out, trace
    return
  }
  abort "unknown primitive function"
}

fn apply-add _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply +"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "+ needs 2 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for + is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  # args->right->left->value
  var right-ah/eax: (addr handle cell) <- get args, right
#?   dump-cell right-ah
#?   abort "aaa"
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "second arg for + is not a number"
    return
  }
  var second-value/edx: (addr float) <- get second, number-data
  # add
  var result/xmm0: float <- copy *first-value
  result <- add *second-value
  new-float out, result
}

fn apply-subtract _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply -"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "- needs 2 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for - is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  # args->right->left->value
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "second arg for - is not a number"
    return
  }
  var second-value/edx: (addr float) <- get second, number-data
  # subtract
  var result/xmm0: float <- copy *first-value
  result <- subtract *second-value
  new-float out, result
}

fn apply-multiply _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply *"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "* needs 2 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for * is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  # args->right->left->value
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "second arg for * is not a number"
    return
  }
  var second-value/edx: (addr float) <- get second, number-data
  # multiply
  var result/xmm0: float <- copy *first-value
  result <- multiply *second-value
  new-float out, result
}

fn apply-divide _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply /"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "/ needs 2 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for / is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  # args->right->left->value
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "second arg for / is not a number"
    return
  }
  var second-value/edx: (addr float) <- get second, number-data
  # divide
  var result/xmm0: float <- copy *first-value
  result <- divide *second-value
  new-float out, result
}

fn apply-square-root _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply sqrt"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "sqrt needs 1 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "arg for sqrt is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  # square-root
  var result/xmm0: float <- square-root *first-value
  new-float out, result
}

fn apply-abs _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply abs"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "abs needs 1 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "arg for abs is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  #
  var result/xmm0: float <- copy *first-value
  var zero: float
  compare result, zero
  {
    break-if-float>=
    var neg1/eax: int <- copy -1
    var neg1-f/xmm1: float <- convert neg1
    result <- multiply neg1-f
  }
  new-float out, result
}

fn apply-sgn _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply sgn"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "sgn needs 1 args but got 0"
    return
  }
  # args->left->value
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "arg for sgn is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  #
  var result/xmm0: float <- copy *first-value
  var zero: float
  $apply-sgn:core: {
    compare result, zero
    break-if-=
    {
      break-if-float>
      var neg1/eax: int <- copy -1
      result <- convert neg1
      break $apply-sgn:core
    }
    {
      break-if-float<
      var one/eax: int <- copy 1
      result <- convert one
      break $apply-sgn:core
    }
  }
  new-float out, result
}

fn apply-car _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply car"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "car needs 1 args but got 0"
    return
  }
  # args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 0/pair
  {
    break-if-=
    error trace, "arg for car is not a pair"
    return
  }
  # car
  var result/eax: (addr handle cell) <- get first, left
  copy-object result, out
}

fn apply-cdr _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply cdr"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "cdr needs 1 args but got 0"
    return
  }
  # args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 0/pair
  {
    break-if-=
    error trace, "arg for cdr is not a pair"
    return
  }
  # cdr
  var result/eax: (addr handle cell) <- get first, right
  copy-object result, out
}

fn apply-cons _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply cons"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "cons needs 2 args but got 0"
    return
  }
  # args->left
  var first-ah/ecx: (addr handle cell) <- get args, left
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  # cons
  new-pair out, *first-ah, *second-ah
}

fn apply-structurally-equal _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply '='"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'=' needs 2 args but got 0"
    return
  }
  # args->left
  var first-ah/ecx: (addr handle cell) <- get args, left
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/edx: (addr handle cell) <- get right, left
  # compare
  var _first/eax: (addr cell) <- lookup *first-ah
  var first/ecx: (addr cell) <- copy _first
  var second/eax: (addr cell) <- lookup *second-ah
  var match?/eax: boolean <- cell-isomorphic? first, second, trace
  compare match?, 0/false
  {
    break-if-!=
    nil out
    return
  }
  new-integer out, 1/true
}

fn apply-< _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply '<'"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'<' needs 2 args but got 0"
    return
  }
  # args->left
  var first-ah/ecx: (addr handle cell) <- get args, left
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/edx: (addr handle cell) <- get right, left
  # compare
  var _first/eax: (addr cell) <- lookup *first-ah
  var first/ecx: (addr cell) <- copy _first
  var first-type/eax: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for '<' is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  var first-float/xmm0: float <- copy *first-value
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "first arg for '<' is not a number"
    return
  }
  var second-value/eax: (addr float) <- get second, number-data
  compare first-float, *second-value
  {
    break-if-float<
    nil out
    return
  }
  new-integer out, 1/true
}

fn apply-> _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply '>'"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'>' needs 2 args but got 0"
    return
  }
  # args->left
  var first-ah/ecx: (addr handle cell) <- get args, left
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/edx: (addr handle cell) <- get right, left
  # compare
  var _first/eax: (addr cell) <- lookup *first-ah
  var first/ecx: (addr cell) <- copy _first
  var first-type/eax: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for '>' is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  var first-float/xmm0: float <- copy *first-value
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "first arg for '>' is not a number"
    return
  }
  var second-value/eax: (addr float) <- get second, number-data
  compare first-float, *second-value
  {
    break-if-float>
    nil out
    return
  }
  new-integer out, 1/true
}

fn apply-<= _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply '<='"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'<=' needs 2 args but got 0"
    return
  }
  # args->left
  var first-ah/ecx: (addr handle cell) <- get args, left
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/edx: (addr handle cell) <- get right, left
  # compare
  var _first/eax: (addr cell) <- lookup *first-ah
  var first/ecx: (addr cell) <- copy _first
  var first-type/eax: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for '<=' is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  var first-float/xmm0: float <- copy *first-value
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "first arg for '<=' is not a number"
    return
  }
  var second-value/eax: (addr float) <- get second, number-data
  compare first-float, *second-value
  {
    break-if-float<=
    nil out
    return
  }
  new-integer out, 1/true
}

fn apply->= _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply '>='"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'>=' needs 2 args but got 0"
    return
  }
  # args->left
  var first-ah/ecx: (addr handle cell) <- get args, left
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/edx: (addr handle cell) <- get right, left
  # compare
  var _first/eax: (addr cell) <- lookup *first-ah
  var first/ecx: (addr cell) <- copy _first
  var first-type/eax: (addr int) <- get first, type
  compare *first-type, 1/number
  {
    break-if-=
    error trace, "first arg for '>=' is not a number"
    return
  }
  var first-value/ecx: (addr float) <- get first, number-data
  var first-float/xmm0: float <- copy *first-value
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/edx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "first arg for '>=' is not a number"
    return
  }
  var second-value/eax: (addr float) <- get second, number-data
  compare first-float, *second-value
  {
    break-if-float>=
    nil out
    return
  }
  new-integer out, 1/true
}

fn apply-print _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply print"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "print needs 2 args but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'print' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  var stream-storage: (stream byte 0x100)
  var stream/edi: (addr stream byte) <- address stream-storage
  print-cell second-ah, stream, trace
  draw-stream-wrapping-right-then-down-from-cursor-over-full-screen screen, stream, 7/fg, 0/bg
  # return what was printed
  copy-object second-ah, out
}

fn apply-clear _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply clear"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'clear' needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'clear' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  #
  clear-screen screen
}

fn apply-up _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply up"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'up' needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'up' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  #
  move-cursor-up screen
}

fn apply-down _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply 'down'"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'down' needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'down' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  #
  move-cursor-down screen
}

fn apply-left _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply 'left'"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'left' needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'left' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  #
  move-cursor-left screen
}

fn apply-right _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply 'right'"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'right' needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'right' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  #
  move-cursor-right screen
}

fn apply-cr _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply 'cr'"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "'cr' needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'cr' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/ecx: (addr screen) <- copy _screen
  #
  move-cursor-to-left-margin-of-next-line screen
}

fn apply-pixel _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply pixel"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "pixel needs 4 args but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'pixel' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/edi: (addr screen) <- copy _screen
  # x = args->right->left->value
  var rest-ah/eax: (addr handle cell) <- get args, right
  var _rest/eax: (addr cell) <- lookup *rest-ah
  var rest/esi: (addr cell) <- copy _rest
  # TODO: check that rest is a pair
  var second-ah/eax: (addr handle cell) <- get rest, left
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/ecx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "second arg for 'pixel' is not an int (x coordinate)"
    return
  }
  var second-value/eax: (addr float) <- get second, number-data
  var x/edx: int <- convert *second-value
  # y = rest->right->left->value
  var rest-ah/eax: (addr handle cell) <- get rest, right
  var _rest/eax: (addr cell) <- lookup *rest-ah
  rest <- copy _rest
  # TODO: check that rest is a pair
  var third-ah/eax: (addr handle cell) <- get rest, left
  var third/eax: (addr cell) <- lookup *third-ah
  var third-type/ecx: (addr int) <- get third, type
  compare *third-type, 1/number
  {
    break-if-=
    error trace, "third arg for 'pixel' is not an int (y coordinate)"
    return
  }
  var third-value/eax: (addr float) <- get third, number-data
  var y/ebx: int <- convert *third-value
  # color = rest->right->left->value
  var rest-ah/eax: (addr handle cell) <- get rest, right
  var _rest/eax: (addr cell) <- lookup *rest-ah
  rest <- copy _rest
  # TODO: check that rest is a pair
  var fourth-ah/eax: (addr handle cell) <- get rest, left
  var fourth/eax: (addr cell) <- lookup *fourth-ah
  var fourth-type/ecx: (addr int) <- get fourth, type
  compare *fourth-type, 1/number
  {
    break-if-=
    error trace, "fourth arg for 'pixel' is not an int (color; 0..0xff)"
    return
  }
  var fourth-value/eax: (addr float) <- get fourth, number-data
  var color/eax: int <- convert *fourth-value
  pixel screen, x, y, color
  # return nothing
}

fn apply-wait-for-key _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply key"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "key needs 1 arg but got 0"
    return
  }
  # keyboard = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 6/keyboard
  {
    break-if-=
    error trace, "first arg for 'key' is not a keyboard"
    return
  }
  var keyboard-ah/eax: (addr handle gap-buffer) <- get first, keyboard-data
  var _keyboard/eax: (addr gap-buffer) <- lookup *keyboard-ah
  var keyboard/ecx: (addr gap-buffer) <- copy _keyboard
  var result/eax: int <- wait-for-key keyboard
  # return key typed
  new-integer out, result
}

fn wait-for-key keyboard: (addr gap-buffer) -> _/eax: int {
  # if keyboard is 0, use real keyboard
  {
    compare keyboard, 0/real-keyboard
    break-if-!=
    var key/eax: byte <- read-key 0/real-keyboard
    var result/eax: int <- copy key
    return result
  }
  # otherwise read from fake keyboard
  var g/eax: grapheme <- read-from-gap-buffer keyboard
  var result/eax: int <- copy g
  return result
}

fn apply-stream _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply stream"
  allocate-stream out
}

fn apply-write _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply write"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "write needs 2 args but got 0"
    return
  }
  # stream = args->left
  var first-ah/edx: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 3/stream
  {
    break-if-=
    error trace, "first arg for 'write' is not a stream"
    return
  }
  var stream-data-ah/eax: (addr handle stream byte) <- get first, text-data
  var _stream-data/eax: (addr stream byte) <- lookup *stream-data-ah
  var stream-data/ebx: (addr stream byte) <- copy _stream-data
  # args->right->left
  var right-ah/eax: (addr handle cell) <- get args, right
  var right/eax: (addr cell) <- lookup *right-ah
  # TODO: check that right is a pair
  var second-ah/eax: (addr handle cell) <- get right, left
  var second/eax: (addr cell) <- lookup *second-ah
  var second-type/ecx: (addr int) <- get second, type
  compare *second-type, 1/number
  {
    break-if-=
    error trace, "second arg for stream is not a number/grapheme"
    return
  }
  var second-value/eax: (addr float) <- get second, number-data
  var x-float/xmm0: float <- copy *second-value
  var x/eax: int <- convert x-float
  var x-grapheme/eax: grapheme <- copy x
  write-grapheme stream-data, x-grapheme
  # return the stream
  copy-object first-ah, out
}

fn apply-lines _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply lines"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "lines needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'lines' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/edx: (addr screen) <- copy _screen
  # compute dimensions
  var dummy/eax: int <- copy 0
  var height/ecx: int <- copy 0
  dummy, height <- screen-size screen
  var result/xmm0: float <- convert height
  new-float out, result
}

fn apply-abort _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  abort "aa"
}

fn apply-columns _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply columns"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "columns needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'columns' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/edx: (addr screen) <- copy _screen
  # compute dimensions
  var width/eax: int <- copy 0
  var dummy/ecx: int <- copy 0
  width, dummy <- screen-size screen
  var result/xmm0: float <- convert width
  new-float out, result
}

fn apply-width _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply width"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "width needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'width' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/edx: (addr screen) <- copy _screen
  # compute dimensions
  var width/eax: int <- copy 0
  var dummy/ecx: int <- copy 0
  width, dummy <- screen-size screen
  width <- shift-left 3/log2-font-width
  var result/xmm0: float <- convert width
  new-float out, result
}

fn apply-height _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
  trace-text trace, "eval", "apply height"
  var args-ah/eax: (addr handle cell) <- copy _args-ah
  var _args/eax: (addr cell) <- lookup *args-ah
  var args/esi: (addr cell) <- copy _args
  # TODO: check that args is a pair
  var empty-args?/eax: boolean <- nil? args
  compare empty-args?, 0/false
  {
    break-if-=
    error trace, "height needs 1 arg but got 0"
    return
  }
  # screen = args->left
  var first-ah/eax: (addr handle cell) <- get args, left
  var first/eax: (addr cell) <- lookup *first-ah
  var first-type/ecx: (addr int) <- get first, type
  compare *first-type, 5/screen
  {
    break-if-=
    error trace, "first arg for 'height' is not a screen"
    return
  }
  var screen-ah/eax: (addr handle screen) <- get first, screen-data
  var _screen/eax: (addr screen) <- lookup *screen-ah
  var screen/edx: (addr screen) <- copy _screen
  # compute dimensions
  var dummy/eax: int <- copy 0
  var height/ecx: int <- copy 0
  dummy, height <- screen-size screen
  height <- shift-left 4/log2-font-height
  var result/xmm0: float <- convert height
  new-float out, result
}