#
#
# The Nim Compiler
# (c) Copyright 2012 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
# Ropes for the C code generator. Ropes are mapped to `string` directly nowadays.
from pathutils import AbsoluteFile
when defined(nimPreviewSlimSystem):
import std/[assertions, syncio, formatfloat]
type
FormatStr* = string # later we may change it to CString for better
# performance of the code generator (assignments
# copy the format strings
# though it is not necessary)
Rope* = string
proc newRopeAppender*(cap = 80): string {.inline.} =
result = newStringOfCap(cap)
proc freeze*(r: Rope) {.inline.} = discard
proc resetRopeCache* = discard
template rope*(s: string): string = s
proc rope*(i: BiggestInt): Rope =
## Converts an int to a rope.
result = rope($i)
proc rope*(f: BiggestFloat): Rope =
## Converts a float to a rope.
result = rope($f)
proc writeRope*(f: File, r: Rope) =
## writes a rope to a file.
write(f, r)
proc writeRope*(head: Rope, filename: AbsoluteFile): bool =
var f: File = default(File)
if open(f, filename.string, fmWrite):
writeRope(f, head)
close(f)
result = true
else:
result = false
proc prepend*(a: var Rope, b: string) = a = b & a
proc runtimeFormat*(frmt: FormatStr, args: openArray[Rope]): Rope =
var i = 0
result = newRopeAppender()
var num = 0
while i < frmt.len:
if frmt[i] == '$':
inc(i) # skip '$'
case frmt[i]
of '$':
result.add("$")
inc(i)
of '#':
inc(i)
result.add(args[num])
inc(num)
of '0'..'9':
var j = 0
while true:
j = j * 10 + ord(frmt[i]) - ord('0')
inc(i)
if i >= frmt.len or frmt[i] notin {'0'..'9'}: break
num = j
if j > high(args) + 1:
raiseAssert "invalid format string: " & frmt
else:
result.add(args[j-1])
of '{':
inc(i)
var j = 0
while frmt[i] in {'0'..'9'}:
j = j * 10 + ord(frmt[i]) - ord('0')
inc(i)
num = j
if frmt[i] == '}': inc(i)
else:
raiseAssert "invalid format string: " & frmt
if j > high(args) + 1:
raiseAssert "invalid format string: " & frmt
else:
result.add(args[j-1])
of 'n':
result.add("\n")
inc(i)
of 'N':
result.add("\n")
inc(i)
else:
raiseAssert "invalid format string: " & frmt
else:
result.add(frmt[i])
inc(i)
proc `%`*(frmt: static[FormatStr], args: openArray[Rope]): Rope =
runtimeFormat(frmt, args)
template addf*(c: var Rope, frmt: FormatStr, args: openArray[Rope]) =
## shortcut for ``add(c, frmt % args)``.
c.add(frmt % args)
const
bufSize = 1024 # 1 KB is reasonable
proc equalsFile*(s: Rope, f: File): bool =
## returns true if the contents of the file `f` equal `r`.
var
buf: array[bufSize, char] = default(array[bufSize, char])
bpos = buf.len
blen = buf.len
btotal = 0
rtotal = 0
when true:
var spos = 0
rtotal += s.len
while spos < s.len:
if bpos == blen:
# Read more data
bpos = 0
blen = readBuffer(f, addr(buf[0]), buf.len)
btotal += blen
if blen == 0: # no more data in file
result = false
return
let n = min(blen - bpos, s.len - spos)
# TODO There's gotta be a better way of comparing here...
if not equalMem(addr(buf[bpos]), cast[pointer](cast[int](cstring(s))+spos), n):
result = false
return
spos += n
bpos += n
result = readBuffer(f, addr(buf[0]), 1) == 0 and
btotal == rtotal # check that we've read all
proc equalsFile*(r: Rope, filename: AbsoluteFile): bool =
## returns true if the contents of the file `f` equal `r`. If `f` does not
## exist, false is returned.
var f: File = default(File)
result = open(f, filename.string)
if result:
result = equalsFile(r, f)
close(f)