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refactor(parse): update grammar & pkg re-exports
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@postspectacular
postspectacular committed Apr 19, 2020
1 parent 12f2499 commit 3ba8973
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Showing 2 changed files with 51 additions and 46 deletions.
91 changes: 45 additions & 46 deletions packages/parse/src/grammar.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -10,57 +10,49 @@ import { seq } from "./combinators/seq";
import { xform } from "./combinators/xform";
import { defContext } from "./context";
import { ALPHA_NUM } from "./presets/alpha";
import { HEX_DIGIT } from "./presets/digits";
import { ESC, UNICODE } from "./presets/escape";
import { UINT } from "./presets/numbers";
import { WS_0, WS_1 } from "./presets/whitespace";
import { dlit, lit } from "./prims/lit";
import { WS0, WS1 } from "./presets/whitespace";
import { lit, litD } from "./prims/lit";
import { noneOf } from "./prims/none-of";
import { oneOf } from "./prims/one-of";
import { range } from "./prims/range";
import { dstring } from "./prims/string";
import { stringD } from "./prims/string";
import { collect } from "./xform/collect";
import { hoist } from "./xform/hoist";
import { join } from "./xform/join";
import { xfInt } from "./xform/number";
import { xfPrint } from "./xform/print";

const apos = dlit("'");
const dash = dlit("-");

const UNICODE = xform(
seq([dstring("\\u"), repeat(HEX_DIGIT, 4, 4)], "char"),
($, ctx) => (
($!.result = String.fromCharCode(xfInt(16)($, ctx)!.result)), $
)
);
const apos = litD("'");
const dash = litD("-");

const REPEAT = maybe(
alt([
oneOf("?*+", "repeat"),
collect(
seq(
[
dlit("{"),
litD("{"),
UINT,
maybe(hoist(seq([dlit(","), UINT]))),
dlit("}"),
maybe(hoist(seq([litD(","), UINT]))),
litD("}"),
],
"repeatN"
)
),
])
);

const CHAR_OR_ESC = alt([ALPHA_NUM, UNICODE]);
const CHAR_OR_ESC = alt([ALPHA_NUM, UNICODE, ESC]);

const CHAR_RANGE = seq([CHAR_OR_ESC, dash, CHAR_OR_ESC], "charRange");

const CHAR_SEL = seq(
[
dlit("["),
litD("["),
maybe(lit("^", "invert")),
oneOrMore(alt([CHAR_RANGE, UNICODE, noneOf("]", "char")]), "choice"),
dlit("]"),
litD("]"),
REPEAT,
],
"charSel"
Expand All @@ -70,54 +62,61 @@ const LIT = hoist(seq([apos, CHAR_OR_ESC, apos], "char"));

const SYM = join(oneOrMore(alt([ALPHA_NUM, oneOf(".-_$")]), "sym"));

const RULE_REF = seq([dlit("<"), SYM, dlit(">"), REPEAT], "ref");
const RULE_REF = seq([litD("<"), SYM, litD(">"), REPEAT], "ref");

const TERM = alt([RULE_REF, LIT, CHAR_SEL]);

const ALT = seq(
[
dlit("("),
WS_0,
litD("("),
WS0,
TERM,
zeroOrMore(seq([WS_0, dlit("|"), WS_0, TERM])),
WS_0,
dlit(")"),
zeroOrMore(seq([WS0, litD("|"), WS0, TERM])),
WS0,
litD(")"),
REPEAT,
],
"alt"
);

const RULE_XF = hoist(seq([dstring("=>"), WS_1, SYM, WS_1], "xform"));
const RULE_XF = hoist(seq([stringD("=>"), WS1, SYM, WS1], "xform"));

const RULE = seq(
[
WS_0,
WS0,
SYM,
WS_0,
dlit(":"),
oneOrMore(alt([TERM, ALT, WS_1]), "body"),
WS0,
litD(":"),
oneOrMore(alt([TERM, ALT, WS1]), "body"),
maybe(RULE_XF),
dlit(";"),
WS_0,
litD(";"),
WS0,
],
"rule"
);

const GRAMMAR = zeroOrMore(RULE, "rules");

const first = ($: ParseScope<any>) => $.children![0];

const nth = ($: ParseScope<any>, n: number) => $.children![n];

const compile = defmulti<ParseScope<string>, Language, any>(
(scope) => scope.id
(scope) => scope.id,
{
unicode: ["char"],
}
);

compile.addAll({
root: ($, lang) => {
const rules = $.children![0].children!;
const rules = first($).children!;
rules.reduce(
(acc, r) => ((acc[r.children![0].result] = dynamic()), acc),
(acc, r) => ((acc[first(r).result] = dynamic()), acc),
lang.rules
);
for (let r of rules) {
const id = r.children![0].result;
const id = first(r).result;
lang.rules[id].set(compile(r, lang));
}
return lang;
Expand All @@ -130,7 +129,7 @@ compile.addAll({
const c = compile(b, lang);
c && acc.push(c);
}
let parser = acc.length > 1 ? seq(acc) : acc[0];
let parser = acc.length > 1 ? seq(acc, id.result) : acc[0];
if (xfID.result) {
const xf = lang.env[xfID.result];
if (!xf) illegalArgs(`missing xform: ${xfID.result}`);
Expand All @@ -145,9 +144,9 @@ compile.addAll({
return compileRepeat(ref, repeat);
},
alt: ($, lang) => {
const acc: Parser<string>[] = [compile($.children![0], lang)];
for (let c of $.children![1].children!) {
acc.push(compile(c.children![0], lang));
const acc: Parser<string>[] = [compile(first($), lang)];
for (let c of nth($, 1).children!) {
acc.push(compile(first(c), lang));
}
return compileRepeat(
acc.length > 1 ? alt(acc) : acc[0],
Expand All @@ -162,10 +161,10 @@ compile.addAll({
charRange: ($) => {
const [a, b] = $.children!;
console.log(`range: ${a.result} - ${b.result}`);
return range<string>(a.result, b.result);
return range(a.result, b.result);
},
charSel: ($, lang) => {
const choices = $.children![1].children!.map((c) => compile(c, lang));
const choices = nth($, 1).children!.map((c) => compile(c, lang));
const [invert, , repeat] = $.children!;
console.log(`invert: ${invert.result}, repeat: ${repeat.result}`);
let parser = choices.length > 1 ? alt(choices) : choices[0];
Expand All @@ -184,9 +183,9 @@ const compileRepeat = (parser: Parser<string>, rspec: ParseScope<string>) => {
case "?":
return maybe(parser);
case "*":
return join(zeroOrMore(parser));
return zeroOrMore(parser);
case "+":
return join(oneOrMore(parser));
return oneOrMore(parser);
default:
return parser;
}
Expand All @@ -196,7 +195,7 @@ const compileRepeat = (parser: Parser<string>, rspec: ParseScope<string>) => {
return parser;
};

export const defLanguage = (rules: string, env: RuleTransforms = {}) => {
export const defGrammar = (rules: string, env: RuleTransforms = {}) => {
const ctx = defContext(rules);
if (GRAMMAR(ctx)) {
xfPrint(ctx.root, ctx);
Expand Down
6 changes: 6 additions & 0 deletions packages/parse/src/index.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@ export * from "./error";
export * from "./grammar";

export * from "./combinators/alt";
export * from "./combinators/boundary";
export * from "./combinators/check";
export * from "./combinators/discard";
export * from "./combinators/dynamic";
Expand All @@ -12,10 +13,14 @@ export * from "./combinators/maybe";
export * from "./combinators/not";
export * from "./combinators/repeat";
export * from "./combinators/seq";
export * from "./combinators/wrap";
export * from "./combinators/xform";

export * from "./presets/alpha";
export * from "./presets/bits";
export * from "./presets/digits";
export * from "./presets/escape";
export * from "./presets/hex";
export * from "./presets/numbers";
export * from "./presets/whitespace";

Expand All @@ -40,3 +45,4 @@ export * from "./xform/hoist";
export * from "./xform/join";
export * from "./xform/number";
export * from "./xform/print";
export * from "./xform/with-id";

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