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@attrx/role-morphic

v0.2.1

Published

Polymorphic value conversion engine - transform values between multiple representations while preserving semantic identity

Readme

RoleMorphic

Motor de conversão polimórfica de valores.

Um valor pode assumir múltiplas formas (variantes) mantendo sua identidade semântica.

Instalação

pnpm add @attrx/role-morphic

Os 4 Pilares

Cada role implementa 4 operações fundamentais:

| Pilar | Descrição | Exemplo | |-------|-----------|---------| | Convert | Transforma entre variantes | hectare → acre | | Cast | Normaliza input sujo | "100 ha" → 100 | | Validate | Verifica regras semânticas | área ≥ 0 | | Format | Apresenta como string | 2.5 → "2.5 ha" |

Uso Rápido

Import Completo

import { areaRole, lengthRole, colorRole, dateRole, currencyRole } from '@attrx/role-morphic';

// Area
areaRole.convert('hectare', 'acre', 1);         // 2.47105
areaRole.cast('hectare', '100 ha');             // 100
areaRole.validate('hectare', 100);              // { valid: true, errors: [] }
areaRole.format('hectare', 2.5);                // "2.5 ha"

// Length
lengthRole.convert('kilometer', 'mile', 100);   // 62.1371
lengthRole.format('meter', 1500);               // "1500 m"

// Color
colorRole.convert('hex', 'rgb_object', '#ff0000');  // { r: 255, g: 0, b: 0, a: 1 }
colorRole.format('hex', '#ff0000', { uppercase: true });  // "#FF0000"

// Date
dateRole.convert('iso', 'timestamp', '2024-12-05T00:00:00.000Z');  // 1733356800000

// Currency (sem convert - só validate/cast/format)
currencyRole.cast('R$ 1.500,50');               // 1500.50
currencyRole.format(1500.50, { currency: 'BRL' }); // "R$1.500,50"

Import por Pilar (Tree-Shaking)

// Apenas validate (zero dependências!)
import { validateArea } from '@attrx/role-morphic/area/validate';
import { validateDate } from '@attrx/role-morphic/date/validate';

// Apenas convert
import { convertLength, toBaseLength } from '@attrx/role-morphic/length/convert';

// Apenas cast
import { castCurrency, tryCastCurrency } from '@attrx/role-morphic/currency/cast';

// Apenas format
import { formatColor, formatHex } from '@attrx/role-morphic/color/format';

Via RoleMorphic (Registry)

import { RoleMorphic, areaRole, lengthRole } from '@attrx/role-morphic';

const morph = new RoleMorphic();
morph.register('area', areaRole.toSpec());
morph.register('length', lengthRole.toSpec());

// Convert
morph.convert('area:hectare', 'area:acre', 1);        // 2.47105
morph.convert('length:kilometer', 'length:mile', 100); // 62.1371

// Try (Result type)
const result = morph.tryConvert('area:hectare', 'area:acre', 1);
if (result.ok) {
  console.log(result.value);  // 2.47105
}

Estrutura de Arquivos

Cada role segue o padrão:

src/roles/{role}/
├── {Role}Role.ts      # Classe + singleton
├── constants.ts       # Tipos e configurações
├── validate.ts        # Pilar validate (standalone, zero deps)
├── convert.ts         # Pilar convert
├── cast.ts            # Pilar cast
├── format.ts          # Pilar format
├── index.ts           # Exports organizados
└── {Role}Role.test.ts # Testes

API

Funções Standalone (por pilar)

// Validate
validateArea(100);                    // { valid: true, errors: [] }
isValidArea(100);                     // true

// Convert
convertArea('hectare', 'acre', 1);    // 2.47105
toBaseArea('hectare', 1);             // 10000 (→ m²)
fromBaseArea('acre', 10000);          // 2.47105

// Cast
castArea('100 ha');                   // 100
castArea('100 ha', 'acre');           // 247.105 (converte)
tryCastArea('invalid');               // { ok: false, error: '...' }

// Format
formatArea('hectare', 2.5);           // "2.5 ha"
formatArea('hectare', 2.5, { verbose: true }); // "2.5 hectares"

Role Instance Methods

import { areaRole } from '@attrx/role-morphic';

areaRole.convert('hectare', 'acre', 1);
areaRole.cast('hectare', '100 ha');
areaRole.validate('hectare', 100);
areaRole.format('hectare', 2.5);
areaRole.getVariants();               // ['square_meter', 'hectare', ...]
areaRole.hasVariant('hectare');       // true
areaRole.toSpec();                    // RoleSpec para RoleMorphic

Roles Disponíveis

SimpleRoles (Numéricas - 4 pilares)

| Role | Base | Variantes | Exemplo | |------|------|-----------|---------| | Area | square_meter | 12 | hectare, acre, km² | | Length | meter | 17 | km, mile, foot, inch | | Mass | kilogram | 16 | gram, pound, ounce | | Temperature | celsius | 4 | fahrenheit, kelvin | | Volume | liter | 18 | ml, gallon, cup | | Speed | meter_per_second | 7 | km/h, mph, knot | | Time | second | 15 | minute, hour, day | | Energy | joule | 12 | calorie, kwh, btu | | Power | watt | 11 | kw, hp, btu/h | | Pressure | pascal | 12 | bar, psi, atm | | Frequency | hertz | 9 | khz, mhz, rpm | | Angle | degree | 7 | radian, turn, grad | | Digital | byte | 12 | kb, mb, gb, gib |

ComplexRoles (Heterogêneas - 4 pilares)

| Role | Base | Variantes | |------|------|-----------| | Color | rgb_object | hex, rgb_string, hsl_object, hsl_string | | Date | timestamp | iso, epoch |

MetadataRoles (3 pilares - sem convert)

| Role | Pilares | Moedas | |------|---------|--------| | Currency | validate, cast, format | BRL, USD, EUR, GBP, JPY, +15 |

Exemplos por Role

Area

import { areaRole, convertArea, formatArea } from '@attrx/role-morphic';

areaRole.convert('hectare', 'acre', 1);           // 2.47105
convertArea('square_meter', 'hectare', 10000);    // 1
formatArea('hectare', 2.5, { verbose: true });    // "2.5 hectares"

Temperature

import { temperatureRole } from '@attrx/role-morphic';

temperatureRole.convert('celsius', 'fahrenheit', 0);   // 32
temperatureRole.convert('celsius', 'kelvin', 0);       // 273.15
temperatureRole.format('celsius', 25);                 // "25 °C"

Color

import { colorRole, convertColor, hexToRgb } from '@attrx/role-morphic';

// Hex → RGB
convertColor('hex', 'rgb_object', '#ff0000');
// { r: 255, g: 0, b: 0 }

// Convenience functions
hexToRgb('#ff0000');      // { r: 255, g: 0, b: 0 }
hexToHsl('#ff0000');      // { h: 0, s: 100, l: 50 }
isValidColor('#ff0000');  // true
isValidColor('red');      // true (named colors)

Date

import { dateRole, convertDate, formatDate } from '@attrx/role-morphic';

// ISO → Timestamp
convertDate('iso', 'timestamp', '2024-12-05T00:00:00.000Z');
// 1733356800000

// Format with locale
formatDate('iso', '2024-12-05T10:30:00.000Z', {
  dateStyle: 'long',
  locale: 'pt-BR',
});

Currency

import { currencyRole, castCurrency, formatCurrency } from '@attrx/role-morphic';

// Cast (parseia string → número)
castCurrency('R$ 1.500,50');     // 1500.50
castCurrency('$1,000.00');       // 1000
castCurrency('€ 99,99');         // 99.99

// Format (número → string com moeda)
formatCurrency(1500.50, { currency: 'BRL' }); // "R$1.500,50"
formatCurrency(1000, { currency: 'USD' });    // "$1,000.00"

// Validate
currencyRole.validate(100.50);                // { valid: true }
currencyRole.validate(-50);                   // { valid: false } (por padrão)
currencyRole.validate(-50, { allowNegative: true }); // { valid: true }

FormatOptions

Base (todas as roles)

type BaseFormatOptions = {
  decimals?: number;      // Casas decimais
  locale?: string;        // 'pt-BR', 'en-US'
  notation?: 'standard' | 'scientific' | 'compact';
  verbose?: boolean;      // Nome completo vs símbolo
};

Color

type ColorFormatOptions = BaseFormatOptions & {
  uppercase?: boolean;    // #FF0000 vs #ff0000
  includeAlpha?: boolean; // Incluir alpha mesmo quando 1
  compact?: boolean;      // rgb(255,0,0) vs rgb(255, 0, 0)
};

Date

type DateFormatOptions = BaseFormatOptions & {
  dateStyle?: 'full' | 'long' | 'medium' | 'short';
  timeStyle?: 'full' | 'long' | 'medium' | 'short';
  timeZone?: string;      // 'America/Sao_Paulo', 'UTC'
  dateOnly?: boolean;
  timeOnly?: boolean;
};

Currency

type CurrencyFormatOptions = {
  currency: CurrencyCode; // 'BRL', 'USD', 'EUR', etc.
  locale?: string;
  decimals?: number;
  verbose?: boolean;      // "1.500,50 Brazilian reais"
  hideSymbol?: boolean;
  showPositiveSign?: boolean;
};

Arquitetura

  • Hub-and-Spoke: Toda conversão passa pela variante base (2N vs N² funções)
  • SimpleRole: Para roles numéricas - usa factors para conversão linear
  • ComplexRole: Para roles heterogêneas - cada variante implementa IVariant
  • MetadataRole: Para roles onde o "tipo" é metadata (ex: currency code)

Ver docs/ARCHITECTURE.md para detalhes.

Criando Roles Custom

SimpleRole

import { SimpleRole, SimpleUnitConfig } from '@attrx/role-morphic';

const DISTANCE_UNITS: Record<string, SimpleUnitConfig> = {
  meter: { factor: 1, symbol: 'm' },
  lightyear: { factor: 9.461e15, symbol: 'ly' },
  parsec: { factor: 3.086e16, symbol: 'pc' },
};

class AstronomicalRole extends SimpleRole {
  readonly name = 'astronomical';
  readonly base = 'meter';
  readonly units = DISTANCE_UNITS;
  readonly aliases = { ly: 'lightyear' };
}

const astroRole = new AstronomicalRole();
astroRole.convert('lightyear', 'parsec', 1);  // 0.3066

Via RoleSpec

import { RoleMorphic, RoleSpec } from '@attrx/role-morphic';

const percentSpec: RoleSpec<number> = {
  base: 'decimal',
  variants: {
    decimal: {
      type: 'number',
      toBase: (v) => v,
      fromBase: (v) => v,
    },
    percent: {
      type: 'number',
      toBase: (p) => p / 100,
      fromBase: (d) => d * 100,
    },
  },
};

const morph = new RoleMorphic();
morph.register('percent', percentSpec);
morph.convert('percent:percent', 'percent:decimal', 50);  // 0.5

Testes

pnpm test

Status: 16 roles, 1407 testes

Licença

MIT