codgen refactoring: prepare for alternative string/seq implementations

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/system/sysstr.nim b/lib/system/sysstr.nim
index 7b81f54da..90ae91cf5 100644
--- a/lib/system/sysstr.nim
+++ b/lib/system/sysstr.nim
@@ -94,8 +94,8 @@ proc mnewString(len: int): NimString {.compilerProc.} =
   result.len = len
 
 proc copyStrLast(s: NimString, start, last: int): NimString {.compilerProc.} =
-  var start = max(start, 0)
-  var len = min(last, s.len-1) - start + 1
+  let start = max(start, 0)
+  let len = min(last, s.len-1) - start + 1
   if len > 0:
     result = rawNewStringNoInit(len)
     result.len = len
@@ -104,6 +104,10 @@ proc copyStrLast(s: NimString, start, last: int): NimString {.compilerProc.} =
   else:
     result = rawNewString(len)
 
+proc nimToCStringConv(s: NimString): cstring {.compilerProc, inline.} =
+  if s == nil or s.len == 0: result = cstring""
+  else: result = cstring(addr s.data)
+
 proc copyStr(s: NimString, start: int): NimString {.compilerProc.} =
   result = copyStrLast(s, start, s.len-1)