1 files changed, 52 insertions, 0 deletions
diff --git a/compiler/ndi.nim b/compiler/ndi.nim
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+++ b/compiler/ndi.nim
@@ -0,0 +1,52 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2017 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## This module implements the generation of ``.ndi`` files for better debugging
+## support of Nim code. "ndi" stands for "Nim debug info".
+
+import ast, msgs, ropes, options, pathutils
+
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
+type
+  NdiFile* = object
+    enabled: bool
+    f: File
+    buf: string
+    filename: AbsoluteFile
+    syms: seq[PSym]
+
+proc doWrite(f: var NdiFile; s: PSym; conf: ConfigRef) =
+  f.buf.setLen 0
+  f.buf.addInt s.info.line.int
+  f.buf.add "\t"
+  f.buf.addInt s.info.col.int
+  f.f.write(s.name.s, "\t")
+  f.f.writeRope(s.loc.snippet)
+  f.f.writeLine("\t", toFullPath(conf, s.info), "\t", f.buf)
+
+template writeMangledName*(f: NdiFile; s: PSym; conf: ConfigRef) =
+  if f.enabled: f.syms.add s
+
+proc open*(f: var NdiFile; filename: AbsoluteFile; conf: ConfigRef) =
+  f.enabled = not filename.isEmpty
+  if f.enabled:
+    f.filename = filename
+    f.buf = newStringOfCap(20)
+
+proc close*(f: var NdiFile, conf: ConfigRef) =
+  if f.enabled:
+    f.f = open(f.filename.string, fmWrite, 8000)
+    doAssert f.f != nil, f.filename.string
+    for s in f.syms:
+      doWrite(f, s, conf)
+    close(f.f)
+    f.syms.reset
+    f.filename.reset