git.kianting.info Git - uann/blob - src/index.js

   1 "use strict";
   2 Object.defineProperty(exports, "__esModule", { value: true });
   3 exports.thenDo = exports.charToCodepoint = exports.matchRange = exports.match1Char = void 0;
   4 var fs = require('fs');
   5 /**
   6  * @description
   7  * it returns a function which test if the first char of the `remained` part of
   8  *  the argument of the function is `c`, if it's true, update the `MatchedPair` wrapped
   9  * in `Some`. Otherwise, it returns `None`.
  10  *  * @param c : the char to be test.
  11  * @returns the updated `MatchedPair` wrapped in `Some(x)` or `None`.
  12  */
  13 function match1Char(c) {
  14     return (m) => {
  15         const charToBeMatched = m.remained[0];
  16         if (charToBeMatched === c) {
  17             return { _tag: "Some", value: {
  18                     matched: m.matched + charToBeMatched,
  19                     remained: m.remained.substring(1)
  20                 } };
  21         }
  22         else {
  23             return { _tag: "None" };
  24         }
  25     };
  26 }
  27 exports.match1Char = match1Char;
  28 ;
  29 /**
  30  * @description
  31  * it returns a function which test if the first char of the `remained` part of
  32  *  the argument of the function is between `l` and `u`, if it's true, update the `MatchedPair` wrapped
  33  * in `Some`. Otherwise, it returns `None`.
  34  *  * @param l : lower bound char, 1-char string
  35  *  * @param u : upper bound char, 1-char string
  36  * @returns the updated `MatchedPair` wrapped in `Some(x)` or `None`.
  37  */
  38 function matchRange(l, u) {
  39     let lCodepoint = charToCodepoint(l);
  40     let uCodepoint = charToCodepoint(u);
  41     if (l > u) {
  42         throw new Error("Error: the codepoint of `" + l + "` is not smaller than `" + u + "`)");
  43     }
  44     return (m) => {
  45         const charToBeMatched = m.remained[0];
  46         const codePointToBeMatched = charToCodepoint(charToBeMatched);
  47         if (codePointToBeMatched >= lCodepoint && codePointToBeMatched <= uCodepoint) {
  48             return { _tag: "Some", value: {
  49                     matched: m.matched + charToBeMatched,
  50                     remained: m.remained.substring(1)
  51                 } };
  52         }
  53         else {
  54             return { _tag: "None" };
  55         }
  56     };
  57 }
  58 exports.matchRange = matchRange;
  59 ;
  60 /**
  61  * convert the one-char string to codepoint.
  62  * @param s : the string to code point.
  63  * @returns if `s.length > 1` return error; otherwise, return the codepoint of `s`.
  64  */
  65 function charToCodepoint(s) {
  66     if (s.length > 1) {
  67         throw new Error("Error: the length of input string for " + s + "is " + s.length + `,
  68         however, it should be 1.`);
  69     }
  70     else {
  71         return s.charCodeAt(0);
  72     }
  73 }
  74 exports.charToCodepoint = charToCodepoint;
  75 /**
  76  *  @description thendo(input, f, ...) like
  77  * a ==> f
  78  */
  79 function thenDo(input, f) {
  80     if (input._tag == "None") {
  81         return input;
  82     }
  83     else {
  84         let inner = input.value;
  85         return f(inner);
  86     }
  87 }
  88 exports.thenDo = thenDo;