From a722e739575012ebad8cd0a7d2c12df478a54eb8 Mon Sep 17 00:00:00 2001
From: Tan Kian-ting <chenjt30@gmail.com>
Date: Tue, 5 Sep 2023 23:57:57 +0800
Subject: [PATCH] add a basic tokenzier function & an int tokenizer

---
 src/index.js   | 143 ++++++++++++++++++++++++++++++++++++++++++++-
 src/index.ts   | 154 ++++++++++++++++++++++++++++++++++++++++++++++++-
 tests/index.js |  37 ++++++++++++
 tests/index.ts |  45 +++++++++++++++
 4 files changed, 375 insertions(+), 4 deletions(-)

diff --git a/src/index.js b/src/index.js
index 712af45..a1ef267 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,7 +1,15 @@
 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
-exports.thenDo = exports.charToCodepoint = exports.matchRange = exports.match1Char = void 0;
+exports.tokenize = exports.zeroOrOnceDo = exports.notDo = exports.zeroOrMoreDo = exports.orDo = exports.thenDo = exports.charToCodepoint = exports.matchRange = exports.matchAny = exports.match1Char = void 0;
 var fs = require('fs');
+/**
+ * wrap a x in a `Some(T)`
+ * @param x : variable to be wrapped.
+ * @returns wrapped `x`.
+ */
+function toSome(x) {
+    return { _tag: "Some", value: x };
+}
 /**
  * @description
  * it returns a function which test if the first char of the `remained` part of
@@ -12,6 +20,9 @@ var fs = require('fs');
  */
 function match1Char(c) {
     return (m) => {
+        if (m.remained.length == 0) {
+            return { _tag: "None" };
+        }
         const charToBeMatched = m.remained[0];
         if (charToBeMatched === c) {
             return { _tag: "Some", value: {
@@ -26,6 +37,24 @@ function match1Char(c) {
 }
 exports.match1Char = match1Char;
 ;
+/**
+ *
+ * @param m : the `MatcheePair` to be consumed.
+ * @returns if the length of `m.remained` >= 1; consumes the matchee by 1 char and wraps it in `Some`,
+ * otherwise, returns `None`.
+ */
+function matchAny(m) {
+    if (m.remained.length >= 1) {
+        return { _tag: "Some", value: {
+                matched: m.matched + m.remained[0],
+                remained: m.remained.substring(1)
+            } };
+    }
+    else {
+        return { _tag: "None" };
+    }
+}
+exports.matchAny = matchAny;
 /**
  * @description
  * it returns a function which test if the first char of the `remained` part of
@@ -42,6 +71,9 @@ function matchRange(l, u) {
         throw new Error("Error: the codepoint of `" + l + "` is not smaller than `" + u + "`)");
     }
     return (m) => {
+        if (m.remained.length < 1) {
+            return { _tag: "None" };
+        }
         const charToBeMatched = m.remained[0];
         const codePointToBeMatched = charToCodepoint(charToBeMatched);
         if (codePointToBeMatched >= lCodepoint && codePointToBeMatched <= uCodepoint) {
@@ -75,6 +107,10 @@ exports.charToCodepoint = charToCodepoint;
 /**
  *  @description thendo(input, f, ...) like
  * a ==> f
+ * @param input: the wrapped input.
+ * @param f: the function to be applied.
+ *
+ * @returns:the applied wrapped result `MatcheePair`.
  */
 function thenDo(input, f) {
     if (input._tag == "None") {
@@ -86,3 +122,108 @@ function thenDo(input, f) {
     }
 }
 exports.thenDo = thenDo;
+/**
+ * @description "or", like the regex `( f1 | f2 )` .
+ * It returns a function `f` of which the argument is`x`.
+ * if `f1(x)` is None, then `f` returns `f2(x)`. Otherwise,
+ * `F` returns `f1(x)`.
+ * @param f1 : 1st function to be compared
+ * @param f2 : 2nd function to be compared
+ * @returns:the combined function
+ */
+function orDo(f1, f2) {
+    return (x) => {
+        let f1x = (f1(x));
+        {
+            if (f1x._tag == "None") {
+                return f2(x);
+            }
+            else {
+                return f1x;
+            }
+        }
+    };
+}
+exports.orDo = orDo;
+/**
+* @description repeating matching function `f`
+* zero or more times, like the asterisk `*` in regex `f*` .
+* @param f : the function to be repeated 0+ times.
+* @returns:the combined function
+*/
+function zeroOrMoreDo(f) {
+    return (x) => {
+        var wrapped_old_x = { _tag: "Some", value: x };
+        var wrapped_new_x = wrapped_old_x;
+        while (wrapped_new_x._tag != "None") {
+            wrapped_old_x = wrapped_new_x;
+            wrapped_new_x = thenDo(wrapped_old_x, f);
+        }
+        ;
+        return wrapped_old_x;
+    };
+}
+exports.zeroOrMoreDo = zeroOrMoreDo;
+/**
+* @description Not. like the `^` inside regex of [^f].
+* returns a function `F(x)` such that if  `f(x)` is `None`,
+* returns the x consuming a char; if `f(x)` is not None, F(x)
+* returns `None`.
+* @param f: the function forbidden to be matched.
+* @returns: combined function `F`.
+*/
+function notDo(f) {
+    return (x) => {
+        let wrapped_x = {
+            _tag: "Some",
+            value: x
+        };
+        let f_x = thenDo(wrapped_x, f);
+        if (f_x._tag != "None") {
+            return { _tag: "None" };
+        }
+        else {
+            return thenDo(wrapped_x, matchAny);
+        }
+    };
+}
+exports.notDo = notDo;
+/**
+ * if `x` is matched by `f` once, returns `f(x)`. Otherwise,
+ * returns x
+ * similar to `?` in regex `f?`.
+ * @param f : the function to be matched
+ * @returns return wrapped f(x)
+ */
+function zeroOrOnceDo(f) {
+    return (x) => {
+        var wrapped_old_x = { _tag: "Some", value: x };
+        var wrapped_new_x = thenDo(wrapped_old_x, f);
+        if (wrapped_new_x._tag != "None") {
+            return wrapped_new_x;
+        }
+        else {
+            return wrapped_old_x;
+        }
+    };
+}
+exports.zeroOrOnceDo = zeroOrOnceDo;
+function tokenize(input) {
+    var input_matchee_pair = toSome({ matched: "",
+        remained: input });
+    // integer = ([+]|[-])\d\d?
+    let integer = (x) => {
+        let wrapped_x = toSome(x);
+        let plusMinus = orDo(match1Char('+'), match1Char('-')); // ([+]|[-])
+        let d = matchRange('0', '9'); // \d
+        return thenDo(thenDo(thenDo(wrapped_x, zeroOrOnceDo(plusMinus)), d), zeroOrMoreDo(d));
+    };
+    console.log(input + ", result: ");
+    console.log(thenDo(input_matchee_pair, integer));
+}
+exports.tokenize = tokenize;
+tokenize("+123");
+tokenize("123");
+tokenize("-123");
+tokenize(" 123");
+tokenize("c123");
diff --git a/src/index.ts b/src/index.ts
index 26cd10d..bcd3e10 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,8 +1,17 @@
 var fs = require('fs');
 
-type Some<T> = { _tag: "Some"; value: T };
-type None = {_tag: "None"};
+export type Some<T> = { _tag: "Some"; value: T };
+export type None = {_tag: "None"};
 
+
+/**
+ * wrap a x in a `Some(T)`
+ * @param x : variable to be wrapped.
+ * @returns wrapped `x`.
+ */
+function toSome<T>(x: T): Some<T>{
+    return  { _tag: "Some", value: x};  
+}
 /**
  * @description Like the `Some(a)` and `None` in Rust.
  *
@@ -33,6 +42,9 @@ export type MatcheePair = {matched : string; remained : string};
  */
 export function match1Char(c : string) : (m: MatcheePair) => Maybe<MatcheePair> {
     return (m : MatcheePair)=>{
+        if (m.remained.length == 0){
+            return { _tag: "None" };
+        }
         const charToBeMatched = m.remained[0];
         if (charToBeMatched === c){
             return {_tag: "Some", value :{
@@ -45,6 +57,22 @@ export function match1Char(c : string) : (m: MatcheePair) => Maybe<MatcheePair>
     }
 };
 
+/**
+ * 
+ * @param m : the `MatcheePair` to be consumed.
+ * @returns if the length of `m.remained` >= 1; consumes the matchee by 1 char and wraps it in `Some`,
+ * otherwise, returns `None`.
+ */
+export function matchAny(m : MatcheePair) : Maybe<MatcheePair>{
+    if (m.remained.length >= 1){
+        return {_tag: "Some", value :{
+            matched : m.matched + m.remained[0],
+            remained : m.remained.substring(1)}};
+    }else{
+        return {_tag: "None"};
+    }
+}
+
 /**
  * @description
  * it returns a function which test if the first char of the `remained` part of
@@ -61,7 +89,9 @@ export function matchRange(l : string, u : string) : (m: MatcheePair) => Maybe<M
         throw new Error("Error: the codepoint of `"+l+"` is not smaller than `"+u+"`)");
     }
     return (m : MatcheePair)=>{
-
+        if (m.remained.length < 1){
+            return {_tag : "None"};
+        }
         const charToBeMatched = m.remained[0];
         const codePointToBeMatched = charToCodepoint(charToBeMatched);
         if (codePointToBeMatched >= lCodepoint && codePointToBeMatched <= uCodepoint){
@@ -92,6 +122,10 @@ export function charToCodepoint(s : string): number{
 /**
  *  @description thendo(input, f, ...) like
  * a ==> f
+ * @param input: the wrapped input. 
+ * @param f: the function to be applied.
+ * 
+ * @returns:the applied wrapped result `MatcheePair`.
  */
 export function thenDo<T>(input : Maybe<T>, f : Function) : Maybe<T>{
     if (input._tag == "None"){
@@ -102,3 +136,117 @@ export function thenDo<T>(input : Maybe<T>, f : Function) : Maybe<T>{
         return f(inner);
     }
 }
+
+/**
+ * @description "or", like the regex `( f1 | f2 )` . 
+ * It returns a function `f` of which the argument is`x`.
+ * if `f1(x)` is None, then `f` returns `f2(x)`. Otherwise, 
+ * `F` returns `f1(x)`.
+ * @param f1 : 1st function to be compared
+ * @param f2 : 2nd function to be compared
+ * @returns:the combined function
+ */
+export function orDo<T>(f1 : Function, f2: Function) : (x : T ) => Maybe<T>{
+    return (x) => {
+        let f1x : Maybe<T> = (f1(x));
+        {
+            if (f1x._tag == "None"){
+                return f2(x);
+            }
+            else{
+                return f1x;
+            }
+        }
+    };
+}
+
+
+/**
+* @description repeating matching function `f` 
+* zero or more times, like the asterisk `*` in regex `f*` . 
+* @param f : the function to be repeated 0+ times.
+* @returns:the combined function
+*/
+export function zeroOrMoreDo<T>(f : Function): (x : T) => Maybe<T>{
+    return (x)=>{
+        var wrapped_old_x : Maybe<T> = {_tag: "Some", value : x};
+        var wrapped_new_x : Maybe<T> = wrapped_old_x;
+
+        while (wrapped_new_x._tag != "None"){
+            wrapped_old_x = wrapped_new_x;
+            wrapped_new_x = thenDo(wrapped_old_x, f);
+        };
+
+        return wrapped_old_x;
+    };
+}
+
+/**
+* @description Not. like the `^` inside regex of [^f].
+* returns a function `F(x)` such that if  `f(x)` is `None`,
+* returns the x consuming a char; if `f(x)` is not None, F(x)
+* returns `None`.
+* @param f: the function forbidden to be matched.
+* @returns: combined function `F`.
+*/
+export function notDo<T>(f : Function): (x : T) => Maybe<T>{
+    return (x)=>{
+        let wrapped_x : Maybe<T> = {
+            _tag : "Some",
+            value : x
+        };
+        let f_x = thenDo(wrapped_x, f);
+        
+        if (f_x._tag != "None"){
+            return {_tag:"None"};
+        }else{
+            return thenDo(wrapped_x, matchAny);
+        }
+    };
+}
+
+/**
+ * if `x` is matched by `f` once, returns `f(x)`. Otherwise, 
+ * returns x
+ * similar to `?` in regex `f?`.
+ * @param f : the function to be matched
+ * @returns return wrapped f(x)
+ */
+export function zeroOrOnceDo<T>(f : Function): (x : T) => Maybe<T>{
+    return (x)=>{
+        var wrapped_old_x : Maybe<T> = {_tag: "Some", value : x};
+        var wrapped_new_x = thenDo(wrapped_old_x, f);
+
+        if (wrapped_new_x._tag != "None"){
+            return wrapped_new_x;
+        }else{
+        return wrapped_old_x;
+        }
+    };
+}
+
+
+export function tokenize(input : string){
+    var input_matchee_pair : Maybe<MatcheePair> = toSome(
+        {matched:"",
+        remained: input});
+
+    // integer = ([+]|[-])\d\d?
+    let integer = (x : MatcheePair) => 
+    { let wrapped_x = toSome(x);
+        let plusMinus = orDo(match1Char('+'), match1Char('-')); // ([+]|[-])
+        let d = matchRange('0','9'); // \d
+        return thenDo(thenDo(thenDo(wrapped_x, 
+            zeroOrOnceDo(plusMinus)),d),
+            zeroOrMoreDo(d));
+    }
+    console.log(input+", result: ");
+    console.log(thenDo(input_matchee_pair, integer));
+
+}
+
+tokenize("+123");
+tokenize("123");
+tokenize("-123");
+tokenize(" 123");
+tokenize("c123");
\ No newline at end of file
diff --git a/tests/index.js b/tests/index.js
index 933dfcc..891511c 100644
--- a/tests/index.js
+++ b/tests/index.js
@@ -1,4 +1,6 @@
 "use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const src_1 = require("../src");
 let assert = require("assert");
 let cloMain = require("../src");
 let a = cloMain.match1Char("我");
@@ -9,6 +11,9 @@ assert(example1.value.remained == "的");
 let example2 = a({ matched: "", remained: "妳的" });
 assert(example2._tag == "None");
 let thenDo = cloMain.thenDo;
+let orDo = cloMain.orDo;
+let zeroOrMoreDo = cloMain.zeroOrMoreDo;
+let notDo = cloMain.notDo;
 // composed part x
 let compPart1 = cloMain.match1Char("我");
 let compPart2 = cloMain.match1Char("的");
@@ -20,6 +25,38 @@ assert(doTestRes1.value.remained == "貓");
 let doThenTestee2 = { _tag: "Some", value: { matched: "", remained: "我們" } };
 let doTestRes2 = thenDo(thenDo(doThenTestee2, compPart1), compPart2);
 assert(doTestRes2._tag == "None");
+let doThenTestee3 = { _tag: "Some", value: { matched: "", remained: "我的貓" } };
+let doTestRes3 = thenDo(thenDo(doThenTestee3, orDo(compPart1, compPart2)), compPart2);
+assert(doTestRes3._tag == "Some");
+assert(doTestRes3.value.matched == "我的");
+assert(doTestRes3.value.remained == "貓");
+let doThenTestee4 = { _tag: "Some", value: { matched: "", remained: "的的貓" } };
+let doTestRes4 = thenDo(thenDo(doThenTestee4, orDo(compPart1, compPart2)), compPart2);
+assert(doTestRes4._tag == "Some");
+assert(doTestRes4.value.matched == "的的");
+assert(doTestRes4.value.remained == "貓");
+let doThenTestee5 = { _tag: "Some", value: { matched: "", remained: "的貓" } };
+let doTestRes5 = thenDo(thenDo(doThenTestee5, zeroOrMoreDo(compPart1)), compPart2);
+assert(doTestRes5._tag == "Some");
+assert(doTestRes5.value.matched == "的");
+assert(doTestRes5.value.remained == "貓");
+let doThenTestee6 = { _tag: "Some", value: { matched: "", remained: "我我我的貓" } };
+let doTestRes6 = thenDo(thenDo(doThenTestee6, zeroOrMoreDo(compPart1)), compPart2);
+assert(doTestRes6._tag == "Some");
+assert(doTestRes6.value.matched == "我我我的");
+assert(doTestRes6.value.remained == "貓");
+let doThenTestee7 = { _tag: "Some", value: { matched: "", remained: "我的" } };
+let doTestRes7 = thenDo(thenDo(doThenTestee7, notDo(compPart1)), compPart2);
+assert(doTestRes7._tag == "None");
+let doThenTestee8 = { _tag: "Some", value: { matched: "", remained: "妳的" } };
+let doTestRes8 = thenDo(thenDo(doThenTestee8, notDo(compPart1)), compPart2);
+assert(doTestRes8._tag == "Some");
+assert(doTestRes8.value.matched == "妳的");
+let doThenTestee9 = { _tag: "Some", value: { matched: "", remained: "妳的" } };
+let doTestRes9 = thenDo(doThenTestee9, src_1.matchAny);
+assert(doTestRes9._tag == "Some");
+assert(doTestRes9.value.matched == "妳");
+assert(doTestRes9.value.remained == "的");
 // harfbuzz test
 let harfbuzz = require("../src/harfbuzz.js");
 harfbuzz.harfbuzzTest("123.abc");
diff --git a/tests/index.ts b/tests/index.ts
index a7cefa5..653f3cf 100644
--- a/tests/index.ts
+++ b/tests/index.ts
@@ -1,3 +1,5 @@
+import { matchAny } from "../src";
+
 let assert = require("assert");
 let cloMain = require("../src");
 
@@ -14,6 +16,10 @@ assert(example2._tag == "None");
 
 
 let thenDo = cloMain.thenDo;
+let orDo = cloMain.orDo;
+let zeroOrMoreDo = cloMain.zeroOrMoreDo;
+let notDo = cloMain.notDo;
+
 // composed part x
 let compPart1 = cloMain.match1Char("我");
 let compPart2 = cloMain.match1Char("的");
@@ -29,6 +35,45 @@ let doThenTestee2 = {_tag : "Some",value : {matched: "", remained: "我們"}};
 let doTestRes2 = thenDo(thenDo(doThenTestee2, compPart1), compPart2);
 assert(doTestRes2._tag == "None");
 
+let doThenTestee3 = {_tag : "Some",value : {matched: "", remained: "我的貓"}};
+let doTestRes3 = thenDo(thenDo(doThenTestee3, orDo(compPart1, compPart2)), compPart2);
+assert(doTestRes3._tag == "Some");
+assert(doTestRes3.value.matched == "我的");
+assert(doTestRes3.value.remained == "貓");
+
+let doThenTestee4 = {_tag : "Some",value : {matched: "", remained: "的的貓"}};
+let doTestRes4 = thenDo(thenDo(doThenTestee4, orDo(compPart1, compPart2)), compPart2);
+assert(doTestRes4._tag == "Some");
+assert(doTestRes4.value.matched == "的的");
+assert(doTestRes4.value.remained == "貓");
+
+let doThenTestee5 = {_tag : "Some",value : {matched: "", remained: "的貓"}};
+let doTestRes5 = thenDo(thenDo(doThenTestee5, zeroOrMoreDo(compPart1)), compPart2);
+assert(doTestRes5._tag == "Some");
+assert(doTestRes5.value.matched == "的");
+assert(doTestRes5.value.remained == "貓");
+
+let doThenTestee6 = {_tag : "Some",value : {matched: "", remained: "我我我的貓"}};
+let doTestRes6 = thenDo(thenDo(doThenTestee6, zeroOrMoreDo(compPart1)), compPart2);
+assert(doTestRes6._tag == "Some");
+assert(doTestRes6.value.matched == "我我我的");
+assert(doTestRes6.value.remained == "貓");
+
+let doThenTestee7 = {_tag : "Some",value : {matched: "", remained: "我的"}};
+let doTestRes7 = thenDo(thenDo(doThenTestee7, notDo(compPart1)), compPart2);
+assert(doTestRes7._tag == "None");
+
+let doThenTestee8 = {_tag : "Some",value : {matched: "", remained: "妳的"}};
+let doTestRes8 = thenDo(thenDo(doThenTestee8, notDo(compPart1)), compPart2);
+assert(doTestRes8._tag == "Some");
+assert(doTestRes8.value.matched == "妳的");
+
+let doThenTestee9 = {_tag : "Some",value : {matched: "", remained: "妳的"}};
+let doTestRes9 = thenDo(doThenTestee9, matchAny);
+assert(doTestRes9._tag == "Some");
+assert(doTestRes9.value.matched == "妳");
+assert(doTestRes9.value.remained == "的");
+
 
 // harfbuzz test
 let harfbuzz = require("../src/harfbuzz.js");
-- 
2.39.2