58 lines
1.6 KiB
JavaScript
58 lines
1.6 KiB
JavaScript
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"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.thenDo = exports.charToCodepoint = exports.match1Char = void 0;
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var fs = require('fs');
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/**
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* @description
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* it returns a function which test if the first char of the `remained` part of
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* the argument of the function is `c`, if it's true, update the `MatchedPair` wrapped
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* in `Some`. Otherwise, it returns `None`.
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* * @param c : the char to be test.
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* @returns the updated `MatchedPair` wrapped in `Some(x)` or `None`.
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*/
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function match1Char(c) {
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return (m) => {
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const charToBeMatched = m.remained[0];
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if (charToBeMatched === c) {
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return { _tag: "Some", value: {
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matched: m.matched + charToBeMatched,
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remained: m.remained.substring(1)
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} };
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}
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else {
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return { _tag: "None" };
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}
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};
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}
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exports.match1Char = match1Char;
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;
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/**
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* convert the one-char string to codepoint.
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* @param s : the string to code point.
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* @returns if `s.length > 1` return error; otherwise, return the codepoint of `s`.
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*/
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function charToCodepoint(s) {
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if (s.length > 1) {
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throw new Error("Error: the length of input string for " + s + "is " + s.length + `,
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however, it should be 1.`);
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}
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else {
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return s.charCodeAt(0);
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}
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}
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exports.charToCodepoint = charToCodepoint;
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/**
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* @description thendo(input, f, ...) like
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* a ==> f
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*/
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function thenDo(input, f) {
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if (input._tag == "None") {
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return input;
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}
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else {
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let inner = input.value;
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return f(inner);
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}
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}
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exports.thenDo = thenDo;
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