REPL improvements

lib/impure/rdstdin.nim

@@ -0,0 +1,37 @@
+#
+#
+#            Nimrod's Runtime Library
+#        (c) Copyright 2011 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## This module contains code for reading from `stdin`:idx:. On UNIX the GNU
+## readline library is wrapped and set up to provide default key bindings 
+## (e.g. you can navigate with the arrow keys). On Windows ``system.readLine``
+## is used. This suffices because Windows' console already provides the 
+## wanted functionality.
+
+when defined(Windows):
+  proc ReadLineFromStdin*(prompt: string): string = 
+    ## Reads a line from stdin.
+    stdout.write(prompt)
+    result = readLine(stdin)
+
+else:
+  import readline, history
+    
+  proc ReadLineFromStdin*(prompt: string): string = 
+    var buffer = readline.readLine(prompt)
+    if isNil(buffer): quit(0)
+    result = $buffer
+    if result.len > 0:
+      add_history(buffer)
+    readline.free(buffer)
+
+  # initialization:
+  # disable auto-complete: 
+  discard readline.bind_key('\t'.ord, readline.abort) 
+
+