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spica

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Supervisor, Coroutine, Channel, select, AtomicPromise, Cancellation, Cache, List, Queue, Stack, and some utils.

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import { min } from './alias'; const ASCII = [...Array(256)].reduce<string>((acc, _, i) => acc + String.fromCharCode(i), ''); // 関数に変換可能 const HUFFMAN_64_CODES = new Uint16Array(128).map((_, i) => { // 62|0b1111_1000 // 63|0b1111_1001 // 64|0b1111_1010 // 65|0b1111_1011 // 66|0b1111_1100_000 // 95|0b1111_1111_101 // 96|0b1111_1111_1100_000 switch (true) { case i < 62: return i; case i < 66: return 0b1111_10 << 2 | i - 62; case i < 96: return 0b1111_11 << 5 | i - 66; default: return 0b1111_1111_11 << 5 | i - 96; } }); const HUFFMAN_64_LENS = new Uint8Array(128).map((_, i) => { switch (true) { case i < 62: return 6; case i < 66: return 8; case i < 96: return 11; default: return 15; } }); const NUMBERS = '0123456789'; const ALPHABETS_U = 'EISAROTNLCDUPMGHYBFVKWZXJQ'.split('').reduce<string>((acc, _, i) => acc + String.fromCharCode(0x41 + i), ''); const ALPHABETS_L = 'eisarotnlcdupmghybfvkwzxjq'.split('').reduce<string>((acc, _, i) => acc + String.fromCharCode(0x61 + i), ''); const SYMBOLS_2A = '~#!?$<>\\^`|\t'; const SYMBOLS_1T = `+/-_= :%.,;'"{}[]&*@()\n`; const CONTROLS = [...Array(32)].reduce<string>((acc, _, i) => '\n\t'.includes(String.fromCharCode(i)) ? acc : acc + String.fromCharCode(i), '') + '\x7f'; const CHARSET_64 = `${NUMBERS}${ALPHABETS_U}${ALPHABETS_L}${SYMBOLS_1T}${SYMBOLS_2A}${CONTROLS}`; const ENC_TABLE_64 = CHARSET_64.split('') .reduce((table, c, i) => (table[c.charCodeAt(0)] = i, table), new Uint8Array(128)); const MIN = 6; type Tree = [(string | Tree)?, (string | Tree)?]; const DEC_TABLE_64: (string | Tree)[] = []; build(DEC_TABLE_64, HUFFMAN_64_CODES, HUFFMAN_64_LENS, CHARSET_64); function build(table: (string | Tree)[], codes: Uint16Array | Uint32Array, lens: Uint8Array, charset: string): void { assert(new Set(charset).size === 128 || charset.length === 256); for (let i = 0; i < codes.length; ++i) { const code = codes[i]; let count = lens[i] - MIN; assert(count >= 0); if (count === 0) { table[code] = charset[i]; continue; } let node = (table[code >> count] as Tree) ??= []; assert(typeof node === 'object'); for (; count !== 0; --count) { const b = code & 1 << count - 1 && 1; if (count === 1) { assert(node[b] === undefined); node[b] = charset[i]; } else { node = (node[b] as Tree) ??= []; assert(typeof node === 'object'); } } } } interface Options { target: Uint8Array; start: number; next: number; skip: number; } export function encode(input: string, opts?: Options): string { let output = ''; let table = ENC_TABLE_64; let codes: Uint16Array | Uint32Array = HUFFMAN_64_CODES; let lens = HUFFMAN_64_LENS; let buffer = opts ? 1 << 7 : 0; let count = opts ? 1 : 0; for (let i = opts?.start ?? 0; i < input.length; ++i) { const code = input.charCodeAt(i); const hidx = table[code]; const hcode = codes[hidx]; let hlen = lens[hidx]; while (hlen !== 0) { assert(count < 8); const cnt = min(hlen, 8 - count); assert(cnt > 0); buffer |= (hcode >>> hlen - cnt & (1 << cnt) - 1) << 8 - count - cnt; assert(buffer >>> 8 === 0); count += cnt; assert(count <= 8); hlen -= cnt; assert(hlen >= 0); if (hlen === 0 && opts?.target[code] === 0) { opts.next = opts.start; opts.skip = i + 1; if (output.length === 0) return ''; output += ASCII[buffer | 0xff >>> count]; if (output.length > i + 1 - opts.start) return ''; opts.next = i + 1; return output; } if (count !== 8) continue; output += ASCII[buffer]; buffer = 0; count = 0; } } if (count !== 0) { assert(count < 8); output += ASCII[buffer | 0xff >>> count]; } if (opts) { opts.next = opts.start; opts.skip = input.length; if (output.length > input.length - opts.start) return ''; opts.next = input.length; } return output; } export function decode(input: string, opts?: Options): string { let output = ''; let table = DEC_TABLE_64; let buffer = 0; let count = 0; let node: Tree[0]; for (let i = opts?.start ?? 0; i < input.length; ++i) { buffer <<= 8; buffer |= input.charCodeAt(i); count += 8; assert(count <= 32); if (i === opts?.start) { count -= 1; } while (count !== 0) { if (node === undefined) { if (count < MIN) break; node = table[buffer >> count - MIN & (1 << MIN) - 1]; if (typeof node === 'string') { if (opts?.target[node.charCodeAt(0)] === 0) { output += node; opts.next = i + 1; return output; } output += node; node = undefined; } count -= MIN; } else { assert(node = node as Tree); const b = buffer & 1 << count - 1 && 1; node = node[b]; if (typeof node === 'string') { if (opts?.target[node.charCodeAt(0)] === 0) { output += node; opts.next = i + 1; return output; } output += node; node = undefined; } --count; } } } if (opts) { opts.next = input.length; } return output; }