Remove Trigraph from given source code

TrigraphRemover.groovy

// Removing trigraph notation in the source code
//----------------------------------------------------------------------------
//| trigraph | replacement | trigraph | replacement | trigraph | replacement |
//----------------------------------------------------------------------------
//| ??=      | #           | ??(      | [           | ??<      | {           |
//| ??/      | \           | ??)      | ]           | ??>      | }           |
//| ??’     | ?           | ??!      | |           | ??-      | ?           |
//----------------------------------------------------------------------------
// From   To
// ??=    #
// ??(    [
// ??)    ]
// ??<    {
// ??>    }
// ??/    \ 
// ??'    ^
// ??!    |
// ??-    ~

String.metaClass.delTrigraph = {  ->
    ans = delegate  
		if (ans =~/\?\?</) {
			ans = ans.replaceAll(/\?\?</) {m0 -> "{"}
        }  //   {
		if (ans =~/\?\?>/) {
			ans = ans.replaceAll(/\?\?>/) {m0 -> "}"}
        } //    }
		if (ans =~/\?\?=/) {
			ans = ans.replaceAll(/\?\?=/) {m0 -> "#"}
        } //    #
		if (ans =~/\?\?\(/) {
			ans = ans.replaceAll(/\?\?\(/) {m0 -> "["}
        } //    [
		if (ans =~/\?\?\)/) {
			ans = ans.replaceAll(/\?\?\)/) {m0 -> "]"}
        } //    ]
		if (ans =~/\?\?\//) {
			ans = ans.replaceAll(/\?\?\//) {m0 -> "\\"}
        } //    \ 
		if (ans =~/\?\?'/) {
			ans = ans.replaceAll(/\?\?'/) {m0 -> "^"}
        } //    ^
		if (ans =~/\?\?!/) {
			ans = ans.replaceAll(/\?\?!/) {m0 -> "|"}
        } //    |  
		if (ans =~/\?\?-/) {
			ans = ans.replaceAll(/\?\?-/) {m0 -> "~"}
        } //    ~ 
    return ans
}
assert "??<".delTrigraph() == "{"
assert "??>".delTrigraph() == "}"
assert "??=".delTrigraph() == "#"
assert "??/".delTrigraph() == """\\"""
assert "??(".delTrigraph() == "["
assert "??)".delTrigraph() == "]"
assert "??'".delTrigraph() == "^"
assert "??!".delTrigraph() == "|"
assert "??-".delTrigraph() == "~"


new File(".").eachFileRecurse { file -> 
    //	if(file.isFile() && file.name.matches("[0-9@_#A-Z]+")) { 
	if(file.isFile() && (file.name.endsWith(".c") ||
                         file.name.endsWith(".h"))
	  ) { 
		println file.getName()
		curName = file.getPath().replaceAll(/.\\(.*)/) {m0,m1 -> m1}
		newName = new File(curName+"_convd")
		convert2(curName, newName)
	}
}

def convert2(from, too) {
	try {
		inpfile = new File(curName.toString()).getText('Shift_JIS')
        outfile = new File(newName.toString())
		inpfile.eachLine { line ->
	   outl = line.delTrigraph().delTrigraph()
	      if ((outl.toString()  =~/\\$/)) {  // if terminated with \ 
              outfile << outl.toString().substring(0, outl.length()-1)
          } else {
              outfile << outl.toString()
              outfile << "\n"
	      }
		}
    } catch (IOException e) {
	     System.out.println(e.getMessage());
	}
}