= Lines of Code Example =

''Part of'' StandardLibraryCategory

== Description ==

This example counts the number of lines for each file that matches the filter in the specified folder.

To make it easier to implement, it counts comments (though it does try to exclude blank lines). I would only use this to get a rough idea of the complexity of various files. Learn more about the pros and cons of measuring lines of code at [http://en.wikipedia.org/wiki/Source_lines_of_code Wikipedia].


== Example ==

{{{
#!d
import std.file;
import std.stdio;
import std.stream;
import std.string;
import std.regexp;


const char[] pgmName = "LinesOfCodeExample";

char[] outputData;


int main(char[][] args)
{
    char[] patternStr;
    char[] pathStr;
    char[] outputFileStr;

    if(args.length < 3)
    {
        writefln("Usage: " ~ pgmName ~ " pattern input_path output_file");
        return 0;
    }
    else
    {
        patternStr = args[1];
        pathStr = args[2];
        outputFileStr = args[3];
    }

    int n = listdirfn(pathStr, patternStr);

    writef("Number: %s\n", n);

    std.file.write(outputFileStr, cast(byte[])outputData);

    return 0;
}


int listdirfn(char[] pathname, char[] pattern)
{
    auto r = new RegExp(pattern, "i");
    int n;

    File fl;

    bool callback(DirEntry* de)
    {
        if (de.isdir)
            std.file.listdir(de.name, & callback);
        else
        {   if (r.test(de.name))
            {
                writefln("%s", de.name);
                n++;

                fl = new File(de.name);
                int cntLn = 0;

                while (!fl.eof())
                {
                    char[] line = strip(fl.readLine());
                    if(line != "") /* don't count empty lines */
                        cntLn++;                    
                }
                fl.close();                 
                outputData ~= `"` ~ de.name ~ `","` ~ toString(cntLn) ~ `"` ~ \r\n;
            }
        }
        return true; // continue
    }

    std.file.listdir(pathname, & callback);
    return n;
}
}}}


== Sample batch file ==

{{{
@echo off
dmd LinesOfCodeExample.d
LinesOfCodeExample.exe "\.(h|hpp|bak|d|vbs|c|cpp|exe)$" C:\w32api-3.1\include C:\examples\loc.csv
pause	
}}}


== Source ==

Partially based on [http://www.digitalmars.com/pnews/read.php?server=news.digitalmars.com&group=digitalmars.D&artnum=33287 digitalmars.D/33287] (listdir example).