Data commit

Task/Execute-Brain-/Nim/execute-brain-.nim

@@ -0,0 +1,32 @@
+import os
+
+var
+  code = if paramCount() > 0: readFile paramStr 1
+         else: readAll stdin
+  tape = newSeq[char]()
+  d    = 0
+  i    = 0
+
+proc run(skip = false): bool =
+  while d >= 0 and i < code.len:
+    if d >= tape.len: tape.add '\0'
+
+    if code[i] == '[':
+      inc i
+      let p = i
+      while run(tape[d] == '\0'): i = p
+    elif code[i] == ']':
+      return tape[d] != '\0'
+    elif not skip:
+      case code[i]
+      of '+': inc tape[d]
+      of '-': dec tape[d]
+      of '>': inc d
+      of '<': dec d
+      of '.': stdout.write tape[d]
+      of ',': tape[d] = stdin.readChar
+      else: discard
+
+    inc i
+
+discard run()