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✨ feat: Add parsing methods.
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‎package.json

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@@ -32,6 +32,7 @@
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},
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"devDependencies": {
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"@aureooms/js-integer": "6.0.0",
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"@aureooms/js-integer-big-endian": "^8.0.0",
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"@aureooms/js-number": "3.1.0",
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"@aureooms/js-prime": "4.0.0",
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"@babel/cli": "7.8.4",

‎src/_constants.js

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@@ -0,0 +1,4 @@
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export const DECIMAL_PREFIX = '.' ;
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export const REPETEND_PREFIX = '|' ;
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export const FRACTION_SEP = '/' ;

‎src/_parse_fixed_point.js

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import { DECIMAL_PREFIX , REPETEND_PREFIX } from './_constants' ;
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export function _parse_fixed_point ( { _chr , reg , sub } ) {
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return function ( base , s ) {
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const [ integral , decimal ] = s.split(DECIMAL_PREFIX) ;
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const [ transient , repetend ] = decimal.split(REPETEND_PREFIX) ;
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const _integral = integral === '0' ? '' : integral ;
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const _repetend = repetend || '' ;
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const _denominator = ( !_repetend ?
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_chr(1) :
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(new Array(repetend.length+1)).join( _chr(base-1) )
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) +
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(new Array(transient.length+1)).join( _chr(0) ) ;
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const _big = _integral + transient + _repetend ;
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const _small = _integral + transient ;
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const _bign = reg(_big, base) ;
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const _smalln = reg(_small, base) ;
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const numerator = _repetend ? sub(_bign, _smalln) : _smalln ;
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const denominator = reg(_denominator, base) ;
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return [ numerator , denominator ] ;
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}
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}

‎src/_parse_fraction.js

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@@ -0,0 +1,14 @@
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import { FRACTION_SEP } from './_constants' ;
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export function _parse_fraction ( { reg } ) {
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return function ( base , s ) {
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const [ _numerator , _denominator ] = s.split(FRACTION_SEP) ;
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return [ reg(_numerator, base), reg(_denominator, base) ] ;
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}
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}

‎src/index.js

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@@ -8,3 +8,5 @@ export * from './cmp_no_bounds' ;
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export * from './simplify' ;
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export * from './digits' ;
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export * from './_stringify_digits' ;
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export * from './_parse_fixed_point' ;
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export * from './_parse_fraction' ;

‎test/src/_fixtures.js

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@@ -1,10 +1,12 @@
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import int from 'int' ;
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import BN from 'bn.js' ;
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import { ZZ } from '@aureooms/js-integer' ;
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import { _chr } from '@aureooms/js-integer-big-endian' ;
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export const ALU = [
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{
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name : 'int',
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anybase: false,
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add : (a, b) => a.add(b),
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sub : (a, b) => a.sub(b),
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mul : (a, b) => a.mul(b),
@@ -23,15 +25,17 @@ export const ALU = [
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divmod : (a,b) => [a.div(b), a.mod(b)],
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divmodn : (a,b) => [a.div(b), a.mod(b)],
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pown : (x,n) => x.pow(n),
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_chr,
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},
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{
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name : 'bn.js',
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anybase: true,
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add : (a, b) => a.add(b),
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sub : (a, b) => a.sub(b),
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mul : (a, b) => a.mul(b),
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muln : (a, b) => a.muln(b),
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div : (a, b) => a.div(b),
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reg : x => new BN(x),
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reg : (x, base) => new BN(x, base),
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str : (x, base) => x.toString(base),
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jz : x => x.eqn(0),
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lt0 : x => x.ltn(0),
@@ -54,15 +58,17 @@ export const ALU = [
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return { u: b.div(gcd), v: a.div(gcd) } ;
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} ,
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pown : (x,n) => x.pow(new BN(n)),
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_chr,
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},
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{
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name : '@aureooms/js-integer',
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anybase: true,
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add : (a, b) => a.add(b),
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sub : (a, b) => a.sub(b),
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mul : (a, b) => a.mul(b),
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muln : (a, b) => a.muln(b),
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div : (a, b) => a.div(b),
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reg : x => ZZ.from(x),
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reg : (x, base) => ZZ.from(x, base),
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str : (x, base) => x.toString(base),
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jz : x => x.iszero(),
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lt0 : x => x.sign() < 0,
@@ -82,6 +88,7 @@ export const ALU = [
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} ;
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},
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pown : (x,n) => x.pown(n),
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_chr,
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}
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];
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‎test/src/core.js

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@@ -4,7 +4,8 @@ import { $2, iadd1, eq0, gt1, divmod } from "@aureooms/js-number" ;
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import {
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_add , _sub , _mul , _div , _pow ,
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_cmp , _cmp_no_bounds ,
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_simplify , _digits , _stringify_digits
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_simplify , _digits , _stringify_digits ,
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_parse_fraction , _parse_fixed_point
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} from '../../src';
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const GOOGOL = '10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000' ;
@@ -70,8 +71,22 @@ function unary ( t , alu , [ [ _x , _y , factory ] , a , b , e ] ) {
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}
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unary.title = ( _ , alu , [ [ name , impl ] , a , b , e ] ) => {
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return `${name}<${impl.name}, ${alu.name}> ${name}(${a}/${b}) = ${e}` ;
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unary.title = ( _ , alu , [ [ name , op , impl ] , a , b , e ] ) => {
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return `${name}<${impl.name}, ${alu.name}> ${name}(${a}/${b}) ${op} ${e}` ;
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} ;
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function macro_parse ( t , alu , [ [ _x , _y , factory ] , base , s , e ] ) {
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const apply = factory( alu );
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const z = apply(base, s)
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t.is(e, z) ;
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}
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macro_parse.title = ( _ , alu , [ [ name , op , impl ] , base , s , e ] ) => {
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return `${name}<${impl.name}, ${alu.name}> ${name}(${base},${s}) ${op} ${e}` ;
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} ;
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const add = [ 'add' , '+' , [ _add ] , binary ] ;
@@ -95,10 +110,28 @@ const stringify_n = b => alu => {
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return ( x , d ) => _stringify_digits( alu.str , b , digits(x, d) ) ;
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} ;
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const stringify_10 = [ 'stringify_10' , '=' , [ stringify_n(10) ] , unary , alu => alu.egcd ] ;
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const stringify_2 = [ 'stringify_2' , '=' , [ stringify_n(2) ] , unary , alu => alu.egcd ] ;
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const stringify_19 = [ 'stringify_19' , '=' , [ stringify_n(19) ] , unary , alu => alu.egcd ] ;
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118+
const parse_fraction = [ 'parse_fraction' , '=' , [
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alu => {
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const repr = x => `${alu.str(x[0])}/${alu.str(x[1])}` ;
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const simp = _simplify(alu) ;
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const parse = _parse_fraction(alu);
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return (base, s) => repr(simp(...parse(base, s))) ;
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}
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] , macro_parse , alu => alu.anybase ] ;
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const parse_fixed_point = [ 'parse_fixed_point' , '=' , [
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alu => {
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const repr = x => `${alu.str(x[0])}/${alu.str(x[1])}` ;
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const simp = _simplify(alu) ;
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const parse = _parse_fixed_point(alu);
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return (base, s) => repr(simp(...parse(base, s))) ;
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}
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] , macro_parse , alu => alu.egcd && alu.anybase ] ;
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const PARAMS = [
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[ add , '3', '4', '1', '4', 1] ,
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[ stringify_19 , '14' , '13', '1.|18ebd2ha475g'] , // HOHO
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[ parse_fraction , 10 , '1/2' , '1/2' ] ,
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[ parse_fraction , 10 , '10/20' , '1/2' ] ,
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[ parse_fixed_point , 19 , '1.|18ebd2ha475g' , '14/13' ] ,
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[ parse_fixed_point , 2 , '0.1' , '1/2' ] ,
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[ parse_fixed_point , 10 , '3.|1415929203539823008849557522123893805309734513274336283185840707964601769911504424778761061946902654867256637168' , '355/113' ] ,
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[ parse_fixed_point , 10 , '0.0|2' , '1/45' ] ,
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] ;
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for (const alu of ALU)

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