compromise/src/result/subset/values/toNumber/findModifiers.js

natural language processing in the browser

'use strict';

//support global multipliers, like 'half-million' by doing 'million' then multiplying by 0.5
const findModifiers = (str) => {
  const mults = [{
      reg: /^(minus|negative)[\s\-]/i,
      mult: -1
    }, {
      reg: /^(a\s)?half[\s\-](of\s)?/i,
      mult: 0.5
    },
    //  {
    //   reg: /^(a\s)?quarter[\s\-]/i,
    //   mult: 0.25
    // }
  ];
  for (let i = 0; i < mults.length; i++) {
    if (str.match(mults[i].reg)) {
      return {
        amount: mults[i].mult,
        str: str.replace(mults[i].reg, '')
      };
    }
  }
  return {
    amount: 1,
    str: str
  };
};

module.exports = findModifiers;