// wink-nlp-utils
// NLP Functions for amplifying negations, managing elisions,
// creating ngrams, stems, phonetic codes to tokens and more.
//
// Copyright (C) GRAYPE Systems Private Limited
//
// This file is part of “wink-nlp-utils”.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//
// ## string
// ### setOfChars
/**
*
* Creates a set of chars from the input string `s`. This is useful
* in even more aggressive string matching using Jaccard or Tversky compared to
* `marker()`. It also has an alias **`soc()`**.
*
* @alias string#setOfChars
* @param {string} str the input string.
* @param {function} [ifn=undefined] a function to build index; it receives the first
* character of `str` and the `idx` as input arguments. The `build()` function of
* [helper.returnIndexer](#helperreturnindexer) may be used as `ifn`. If `undefined`
* then index is not built.
* @param {number} [idx=undefined] the index; passed as the second argument to the `ifn`
* function.
* @return {string} the soc.
* @example
* setOfChars( 'the quick brown fox jumps over the lazy dog' );
* // -> ' abcdefghijklmnopqrstuvwxyz'
*/
var setOfChars = function ( str, ifn, idx ) {
var cset = new Set( str );
if ( typeof ifn === 'function' ) {
ifn( str[ 0 ], idx );
}
return ( cset );
}; // soc()
module.exports = setOfChars;