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"use strict";
const h = require("./helpers");
const PatternMatch = require("./pattern-match");
module.exports = t => {
// small abstractions
const not = node => t.unaryExpression("!", node);
const notnot = node => not(not(node));
const or = (a, b) => t.logicalExpression("||", a, b);
const and = (a, b) => t.logicalExpression("&&", a, b);
function simplifyPatterns(path) {
const test = path.get("test");
const consequent = path.get("consequent");
const alternate = path.get("alternate");
const _h$typeSymbols = h.typeSymbols(t),
EX = _h$typeSymbols.Expression; // Convention:
// ===============
// for each pattern [test, consequent, alternate, handler(expr, cons, alt)]
const matcher = new PatternMatch([[EX, true, false, e => notnot(e)], [EX, false, true, e => not(e)], [EX, true, EX, (e, c, a) => or(notnot(e), a)], [EX, false, EX, (e, c, a) => and(not(e), a)], [EX, EX, true, (e, c) => or(not(e), c)], [EX, EX, false, (e, c) => and(notnot(e), c)]]);
const result = matcher.match([test, consequent, alternate], h.isPatternMatchesPath(t));
if (result.match) {
path.replaceWith(result.value(test.node, consequent.node, alternate.node));
}
}
return {
simplifyPatterns
};
};
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