X-Git-Url: https://git.kianting.info/?a=blobdiff_plain;f=src%2Ftokenize.ts;fp=src%2Ftokenize.ts;h=861b638e32420fc41b677eb943cd24d47eff601a;hb=cda463d89022d09a5273b59bcd3e776f1127697a;hp=0000000000000000000000000000000000000000;hpb=aefa3e14791ba05b7959572338ad2377f528ab0b;p=uann

diff --git a/src/tokenize.ts b/src/tokenize.ts
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--- /dev/null
+++ b/src/tokenize.ts
@@ -0,0 +1,542 @@
+
+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: @, {, }.
+
+}
+
+