-import * as util from 'util';
-
-var fs = require('fs');
-
-export type Some<T> = { _tag: "Some"; value: T };
-export type None = { _tag: "None" };
-/**
- * part for tokenize the input string
- */
-
-/**
- * wrap a x in a `Some(T)`
- * @param x : variable to be wrapped.
- * @returns wrapped `x`.
- */
-export function toSome<T>(x: T): Some<T> {
- return { _tag: "Some", value: x };
-}
-/**
- * @description Like the `Some(a)` and `None` in Rust.
- *
- * @example
- * ```ts
- * let exam1 : Maybe<Number> = { _tag: "Some", value: 12 };
- * let exam2 : Maybe<Number> = None;
- * ```
- */
-export type Maybe<T> = Some<T> | None;
-
-
-/**
- * @description
- * the pair of the string to be matched later and the string that have been matched
- * @var matched : have been matched
- * @var remained : will be tested whether it'll be matched.
- * @var matched_type (optional): the type of the matched string
-*/
-export interface MatcheePair {
- matched: string
- remained: string
- matched_type?: TokenType
-}
-
-/**
- * The types of Token
- * NL, // newline
- *
- * SP, // half-width space and tab
- *
- * ID, // identifier
- *
- * STR, // string
- *
- * OP, // operator or something like it
- *
- * FLO, // float num
- *
- * INT, // integer
- *
- * I_* // integer manipulation
- *
- * F_* // float manipulation
- *
- * SEMI_C// semi-colon
- */
-export enum TokenType {
- NL, // newline
- SP, // half-width space and tab
- ID, // identifier
- STR, // string
- FLO, // float num
- INT, // integer
- F_ADD,
- F_SUB,
- F_MUL,
- F_DIV,
- I_ADD,
- I_SUB,
- I_MUL,
- I_DIV,
- L_PAREN, // (
- R_PAREN, // )
- L_BRACK, // [
- R_BRACK, // ]
- L_BRACE, // {
- R_BRACE, // }
- COMMA, // ,
- DOT, // .
- COLON, // :
- SEMI_C, // ;
- AT, // @
- HASH, // #
- EQ, // ==
- SET, // =
- GT, // > greater than
- LT, // <less than
- GE, // >=
- LE, // <=
- NE, // <>
- APOS, // '
- R_ARROW, // ->
- TRUE, // true
- FALSE, // false
- IF, // if
-}
-
-/**
- * tokenized token.
- * @var text : the content text
- * @var type (optional): the type of the token
- * @var col : the column number
- * @var ln : the line number
- */
-export interface Token {
- text: string,
- type?: TokenType,
- col: number,
- ln: number,
-}
-
-/**
- * @description
- * it returns a function which test if the first char of the `remained` part of
- * the argument of the function is `c`, if it's true, update the `MatchedPair` wrapped
- * in `Some`. Otherwise, it returns `None`.
- * * @param c : the char to be test.
- * @returns the updated `MatchedPair` wrapped in `Some(x)` or `None`.
- */
-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: {
- matched: m.matched + charToBeMatched,
- remained: m.remained.substring(1)
- }
- };
- }
- else {
- return { _tag: "None" };
- }
- }
-};
-
-/**
- *
- * @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
- * the argument of the function is between `l` and `u`, if it's true, update the `MatchedPair` wrapped
- * in `Some`. Otherwise, it returns `None`.
- * * @param l : lower bound char, 1-char string
- * * @param u : upper bound char, 1-char string
- * @returns the updated `MatchedPair` wrapped in `Some(x)` or `None`.
- */
-export function matchRange(l: string, u: string): (m: MatcheePair) => Maybe<MatcheePair> {
- let lCodepoint = charToCodepoint(l);
- let uCodepoint = charToCodepoint(u);
- if (l > u) {
- 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) {
- return {
- _tag: "Some", value: {
- matched: m.matched + charToBeMatched,
- remained: m.remained.substring(1)
- }
- };
- }
- else {
- return { _tag: "None" };
- }
- }
-};
-
-
-/**
- * check if a matcheePair `m` matches a stringv `s`.
- * @param s the checker string.
- * @returns `None` or matched pair wrapped in `Some`
- */
-export function matchWord(s: string, ): (m: MatcheePair) => Maybe<MatcheePair> {
- return (m)=>{
- if (s.length==0){
- return { _tag: "None" };
- }
- var someM : Maybe<MatcheePair> = toSome(m);
- for (var idx : number=0; idx<s.length; idx++){
- someM = thenDo(someM, match1Char(s[idx]))
- }
- return someM;
- }
-}
-
-/**
- * convert the one-char string to codepoint.
- * @param s : the string to code point.
- * @returns if `s.length > 1` return error; otherwise, return the codepoint of `s`.
- */
-export function charToCodepoint(s: string): number {
- if (s.length > 1) {
- throw new Error("Error: the length of input string for " + s + "is " + s.length + `,
- however, it should be 1.`);
- } else {
- return s.charCodeAt(0);
- }
-}
-
-/**
- * @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") {
- return input;
- }
- else {
- let inner = input.value;
- 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): Array<Token> {
- var input_matchee_pair: Maybe<MatcheePair> = toSome(
- {
- matched: "",
- remained: input
- });
-
- /**
- * generate a parser of a basic term (b_term)
- * @param pattern : the pattern parser
- * @param token_type : the returning token type
- * @returns a wrapped parser.
- */
- function bTerm(pattern: Function, token_type: TokenType) {
- return (x: MatcheePair) => {
- let wrapped_x = toSome(x);
- let result = pattern(wrapped_x);
- if (result._tag == "Some") {
- result.value.matched_type = token_type;
- }
- return result;
- }
- }
-
- let d = matchRange('0', '9'); // \d
- // [+-]
- let plusMinus = orDo(match1Char('+'), match1Char('-'));
- let s_aux = orDo(match1Char(' '), match1Char('\t')); // (" " | "\t")
-
- // integer = ([+]|[-])?\d\d*
- let integer = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(thenDo(x,
- zeroOrOnceDo(plusMinus)), d),
- zeroOrMoreDo(d)),
- TokenType.INT);
- // space = [ \t]+
- let space = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, s_aux), zeroOrMoreDo(s_aux)),
- TokenType.SP);
-
- // newline = \r?\n
- let newline = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x,
- zeroOrOnceDo(match1Char('\r'))),
- match1Char('\n')),
- TokenType.NL);
-
- // [_A-Za-z]
- let idHead = orDo(orDo(matchRange('a', 'z'), matchRange('A', 'Z')), match1Char('_'));
- let idRemained = orDo(idHead, matchRange('0', '9')); // [_A-Za-z0-9]
-
- // id = [_A-Za-z][_A-Za-z0-9]*
- let id = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x,
- idHead),
- zeroOrMoreDo(idRemained)),
- TokenType.ID);
- let doublequote = match1Char("\"");
- // [\\][\"]
- let escapeReverseSlash = (x: MatcheePair) =>
- thenDo(thenDo(toSome(x), match1Char("\\")), doublequote);
- // ([\\]["]|[^\"])*
- let stringInnerPattern = zeroOrMoreDo(
- orDo(escapeReverseSlash, notDo(match1Char("\""))));
-
- // str = ["]([\\]["]|[^"])*["]
- let str = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(thenDo(x, doublequote),
- stringInnerPattern), doublequote),
- TokenType.STR);
-
- // float = [+-]?\d+[.]\d+
- function floatPattern(x: Maybe<MatcheePair>) {
- return thenDo(thenDo(thenDo(thenDo(thenDo(thenDo(x,
- zeroOrOnceDo(plusMinus)), d),
- zeroOrMoreDo(d)),
- match1Char(".")), d),
- zeroOrMoreDo(d))
- };
- let float = bTerm(floatPattern, TokenType.FLO);
-
- // operators
- // +.
- let floatAdd = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("+")), match1Char(".")),
- TokenType.F_ADD);
- // +.
- let floatSub = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("-")), match1Char(".")),
- TokenType.F_SUB);
-
- // *.
- let floatMul = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("*")), match1Char(".")),
- TokenType.F_MUL);
-
- // /.
- let floatDiv = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("/")), match1Char(".")),
- TokenType.F_DIV);
-
- // ==
- let eq = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("=")), match1Char("=")),
- TokenType.EQ);
-
- // >=
- let ge = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char(">")), match1Char("=")),
- TokenType.GE);
-
- // <=
- let le = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("<")), match1Char("=")),
- TokenType.LE);
-
- // !=
- let ne = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("!")), match1Char("=")),
- TokenType.NE);
-
- // ->
- let rightArrow = bTerm((x: Maybe<MatcheePair>) =>
- thenDo(thenDo(x, match1Char("-")), match1Char(">")),
- TokenType.R_ARROW);
-
-
- /**
- * unary operator : generating the pattern of basic unary operator
- * @param char : uniry char for the operator
- * @param token_type : the corresponding token_type
- */
- function unaryOp(char: string, token_type: TokenType) {
- return bTerm((x: Maybe<MatcheePair>) => thenDo(x, match1Char(char)),
- token_type);
- };
-
- let intAdd = unaryOp('+', TokenType.I_ADD);
- let intSub = unaryOp('-', TokenType.I_SUB);
- let intMul = unaryOp('*', TokenType.I_MUL);
- let intDiv = unaryOp('/', TokenType.I_DIV);
- let lParen = unaryOp('(', TokenType.L_PAREN);
- let rParen = unaryOp(')', TokenType.R_PAREN);
- let lBracket = unaryOp('[', TokenType.L_BRACK);
- let rBracket = unaryOp(']', TokenType.R_BRACK);
- let lBrace = unaryOp('{', TokenType.L_BRACE);
- let rBrace = unaryOp('}', TokenType.R_BRACE);
- let comma = unaryOp(',', TokenType.COMMA);
- let dot = unaryOp('.', TokenType.DOT);
- let colon = unaryOp(':', TokenType.COLON);
- let semicolon = unaryOp(';', TokenType.SEMI_C);
- let at = unaryOp('@', TokenType.AT);
- let hash = unaryOp('#', TokenType.HASH);
- let set = unaryOp('=', TokenType.SET);
- let greaterthan = unaryOp('>', TokenType.GT);
- let lessthan = unaryOp('<', TokenType.LE);
- let apos = unaryOp('\'', TokenType.APOS);
-
-
-
- let term = (token_list: Array<Token>, x: Some<MatcheePair>) => {
- var ln = 1;
- var col = 0;
- var old_x = x;
- let term_list = [
- floatAdd, floatSub, floatMul, floatDiv,
- intAdd, intSub, intMul, intDiv,
- eq, ge, le, ne, rightArrow,
- lParen, rParen, lBracket, rBracket, lBrace, rBrace,
- comma, dot, colon, semicolon, at, hash,
- set, greaterthan, lessthan, apos,
- float, newline, space, id, integer, str];
- let term_aux = term_list.reduce((x, y) => orDo(x, y));
-
- var new_x: Maybe<MatcheePair> = thenDo(old_x, term_aux);
- while (new_x._tag != "None") {
- if (new_x.value.matched_type != TokenType.NL) {
- col += new_x.value.matched.length;
- token_list.push({
- text: new_x.value.matched,
- type: new_x.value.matched_type,
- ln: ln,
- col: col
- });
-
- }
- else {
- col = 0;
- ln += 1;
-
- token_list.push({
- text: new_x.value.matched,
- type: new_x.value.matched_type,
- ln: ln,
- col: col
- });
-
- }
-
-
- old_x = toSome({
- matched: "",
- remained: new_x.value.remained
- });
- new_x = thenDo(old_x, term_aux);
- }
-
- if (old_x.value.remained.length) {
- console.log(token_list);
- throw new Error("the code can't be tokenized is near Ln. " + ln + ", Col." + col
- + ", starting with " + old_x.value.remained.substring(0, 10));
- }
-
- return token_list;
- }
-
- return term([], input_matchee_pair);
-
- // TODO: id, string, space, basic operator, 3 marks: @, {, }.
-
-}
-
-