7784 - baremetal/shell: start of trace

3 files changed, 56 insertions, 11 deletions

diff --git a/baremetal/shell/read.mu b/baremetal/shell/read.mu
index d6325c62..5c6014d9 100644
--- a/baremetal/shell/read.mu
+++ b/baremetal/shell/read.mu
@@ -1,5 +1,5 @@
 # out is not allocated
-fn read-cell in: (addr gap-buffer), out: (addr handle cell) {
+fn read-cell in: (addr gap-buffer), out: (addr handle cell), trace: (addr trace) {
   # TODO:
   #   tokenize
   #   insert parens
@@ -13,13 +13,16 @@ fn read-cell in: (addr gap-buffer), out: (addr handle cell) {
     var done?/eax: boolean <- gap-buffer-scan-done? in
     compare done?, 0/false
     break-if-!=
-    next-token in, token
+    next-token in, token, trace
+    var error?/eax: boolean <- has-errors? trace
+    compare error?, 0/false
+    break-if-!=
     read-symbol token, out
     loop
   }
 }
 
-fn next-token in: (addr gap-buffer), out: (addr stream byte) {
+fn next-token in: (addr gap-buffer), out: (addr stream byte), trace: (addr trace) {
   clear-stream out
   skip-whitespace-from-gap-buffer in
   var g/eax: grapheme <- peek-from-gap-buffer in
@@ -27,13 +30,13 @@ fn next-token in: (addr gap-buffer), out: (addr stream byte) {
     var digit?/eax: boolean <- is-decimal-digit? g
     compare digit?, 0/false
     break-if-=
-    next-number-token in, out
+    next-number-token in, out, trace
     return
   }
-  next-symbol-token in, out
+  next-symbol-token in, out, trace
 }
 
-fn next-symbol-token in: (addr gap-buffer), out: (addr stream byte) {
+fn next-symbol-token in: (addr gap-buffer), out: (addr stream byte), trace: (addr trace) {
   {
     var done?/eax: boolean <- gap-buffer-scan-done? in
     compare done?, 0/false
@@ -101,7 +104,7 @@ fn is-symbol-grapheme? g: grapheme -> _/eax: boolean {
   return 1/true
 }
 
-fn next-number-token in: (addr gap-buffer), out: (addr stream byte) {
+fn next-number-token in: (addr gap-buffer), out: (addr stream byte), trace: (addr trace) {
   var done?/eax: boolean <- gap-buffer-scan-done? in
   compare done?, 0/false
   break-if-!=
diff --git a/baremetal/shell/sandbox.mu b/baremetal/shell/sandbox.mu
index c89814d4..6ba2e4ac 100644
--- a/baremetal/shell/sandbox.mu
+++ b/baremetal/shell/sandbox.mu
@@ -1,6 +1,7 @@
 type sandbox {
   data: (handle gap-buffer)
   value: (handle stream byte)
+  trace: (handle trace)
 }
 
 fn initialize-sandbox _self: (addr sandbox) {
@@ -94,17 +95,26 @@ fn edit-sandbox _self: (addr sandbox), key: byte {
     var _data/eax: (addr gap-buffer) <- lookup *data-ah
     var data/ecx: (addr gap-buffer) <- copy _data
     var value-ah/eax: (addr handle stream byte) <- get self, value
-    var value/eax: (addr stream byte) <- lookup *value-ah
-    run data, value
+    var _value/eax: (addr stream byte) <- lookup *value-ah
+    var value/edx: (addr stream byte) <- copy _value
+    var trace-ah/eax: (addr handle trace) <- get self, trace
+    var trace/eax: (addr trace) <- lookup *trace-ah
+    run data, value, trace
     return
   }
   add-grapheme-to-sandbox self, g
 }
 
-fn run in: (addr gap-buffer), out: (addr stream byte) {
+fn run in: (addr gap-buffer), out: (addr stream byte), trace: (addr trace) {
   var read-result-storage: (handle cell)
   var read-result/esi: (addr handle cell) <- address read-result-storage
-  read-cell in, read-result
+  read-cell in, read-result, trace
+  var error?/eax: boolean <- has-errors? trace
+  {
+    compare error?, 0/false
+    break-if-=
+    return
+  }
   # TODO: eval
   print-cell read-result, out
 }
diff --git a/baremetal/shell/trace.mu b/baremetal/shell/trace.mu
new file mode 100644
index 00000000..88ee0860
--- /dev/null
+++ b/baremetal/shell/trace.mu
@@ -0,0 +1,32 @@
+# A trace records the evolution of a computation.
+# An integral part of the Mu Shell is facilities for browsing traces.
+
+type trace {
+  curr-depth: int
+  data: (handle stream trace-line)
+}
+
+type trace-line {
+  depth: int
+  label: (handle array byte)
+  data: (handle array byte)
+}
+
+fn has-errors? _self: (addr trace) -> _/eax: boolean {
+  return 0/false
+}
+
+fn trace _self: (addr trace), label: (addr array byte), data: (array stream byte) {
+}
+
+fn new-trace-line depth: int, label: (addr array byte), data: (array stream byte), out: (addr trace-line) {
+}
+
+fn trace-lower _self: (addr trace) {
+}
+
+fn trace-higher _self: (addr trace) {
+}
+
+fn render-trace screen: (addr screen), _self: (addr trace), _x: int, _y: int {
+}