--- /dev/null
+
+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, // newlinw
+ 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, // ->
+
+}
+
+/**
+ * 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" };
+ }
+ }
+};
+
+/**
+ * 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.INT);
+
+ // 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, integer, str, id];
+ 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: @, {, }.
+
+}
+
+
projects / uann / blobdiff