Demangles D symbol names found in standard input.

ddemangle.d

import core.demangle;
import std.ascii;
import std.stdio;

void main() {
  foreach (line; stdin.byLine(File.KeepTerminator.yes)) {
    size_t lastWritten;
    bool hadUnderscore;
    bool inSymbol;

    foreach (i, char c; line) {
      if (!inSymbol && hadUnderscore && c == 'D') {
        inSymbol = true;
        write(line[lastWritten .. (i - 1)]);
        lastWritten = i - 1;
      } else if (inSymbol && !(isAlphaNum(c) || c == '_')) {
        inSymbol = false;
        write(demangle(line[lastWritten .. i]));
        lastWritten = i;
      }

      hadUnderscore = (c == '_');
    }

    auto rest = line[lastWritten .. $];
    if (inSymbol) {
      write(demangle(rest));
    } else {
      write(rest);
    }
  }
}