File replace01.txt is to be included in output file.

// BUILD_INCLUDE("./scratch/replace1.txt")[comment?type=Single, breakstring?width=75&flags=word&eol=none]

[comment?type=Single, breakstring?width=75&flags=word&eol=none]

The option comments allow for input file content to be treated as comments in the output.

type=Single Pads the left side of each line with // and a single space.
See: Enum values for commentkind for possible types.

The various options of breakstring allow for the breaking of lines in different ways.
If the width option of breakstring is not set then width defaults to 80.

Width=# where as # is a number, determines that each line will be broken as close to # characers as possible depending other breakstring options.

flags=word determines that lines are not to be broken on a word.

eol=none determines that line breaks are not touched and remain part of the output.

breakstring?width=75&flags=word&eol=none

width=75 determines that breaking of lines is to start at 75 characters.
Due to eol=none the output will break when it gets to width or the end or a line.

module.exports = function (grunt) {
  grunt.initConfig({
    build_include: {
      default: {
        match: 'buildIncludeSlash',
        src: './lib/test.txt',
        dest: './scratch/test.txt'
      }
    }
  });
  grunt.loadNpmTasks('grunt-build-include');
  grunt.registerTask('default', ['build_include:default']);
};

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// whangs jumpy veldt fox.
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// blew my junk TV quiz.
// 
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// Jack!
// " my brave ghost pled. Five quacking zephyrs jolt my wax bed. Flummoxed
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// A
// very bad quack might jinx zippy fowls. Few quips galvanized the mock jury box.
// Quick brown dogs jump over the lazy fox. The jay, pig, fox, zebra, and my wolves
// quack!
// Blowzy red vixens fight for a quick jump. Joaquin Phoenix was gazed
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// ", Alex Trebek's fun TV quiz game. Woven silk pyjamas exchanged for blue quartz.