#nashorn word histogram of a file

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/*
 * This example demonstrates how to print word histogram
 * of a given text file using regex, array and JSON
 * functions.
 */

if (arguments.length < 1) {
    print("Usage: jjs -scripting word_histogram.js -- <file>");
    exit(1);
}

var obj = {};

readFully(arguments[0]).
    split(/[^\w+]/).
    forEach(function(x)
      (x in obj? obj[x]++ : obj[x] = 1));

print(JSON.stringify(obj));