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luhn-generator

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A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

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"use strict"; const VOID_0 = t => t.unaryExpression("void", t.numericLiteral(0), true); const evaluate = require("babel-helper-evaluate-path"); // Types as Symbols - for comparing types const types = {}; // This is a test key which is used to avoid Object.keys check // Object.keys() check is really expensive // https://gist.github.com/vigneshshanmugam/c766550ecd02292dcdfbf0bf013b9d3d const testKey = "Expression"; const typeSymbols = t => { // don't recompute if (types[testKey] !== undefined) { return types; } t.TYPES.forEach(type => { types[type] = Symbol.for(type); }); return types; }; const isNodeOfType = (t, node, typeSymbol) => typeof typeSymbol !== "symbol" ? false : t["is" + Symbol.keyFor(typeSymbol)](node); const isPatternMatchesPath = t => function _isPatternMatchesPath(patternValue, inputPath) { if (Array.isArray(patternValue)) { for (let i = 0; i < patternValue.length; i++) { if (_isPatternMatchesPath(patternValue[i], inputPath)) { return true; } } return false; } if (typeof patternValue === "function") { return patternValue(inputPath); } if (isNodeOfType(t, inputPath.node, patternValue)) return true; const evalResult = evaluate(inputPath); if (!evalResult.confident || !inputPath.isPure()) return false; return evalResult.value === patternValue; }; module.exports = { VOID_0, // Types as Symbols typeSymbols, // This is required for resolving type aliases isNodeOfType, isPatternMatchesPath };