flow-typer-js/dist/types/map.js

Declarative static and runtime type checking with Flow

//      
import { getType } from '../utils.js'
import { validatorError } from '../error.js'
import { EMPTY_VALUE } from '../const.js'
import { undef } from './primitives.js'
import { object } from './object.js'
import { unionOf } from './union.js'

                                       

export const mapOf =       
  (
    keyTypeFn                  ,
    typeFn                  
  )                            => {
    function mapOf (value       , _scope         = 'Map') {
      if (value === EMPTY_VALUE) return {}
      const o = object(value, _scope)
      const reducer = (acc        , key        ) =>
        Object.assign(
          acc,
          {
            // $FlowFixMe
            [keyTypeFn(key, `${_scope}[_]`)]
              :typeFn(o[key], `${_scope}.${key}`)
          }
        )
      return Object.keys(o).reduce(reducer, {})
    }
    mapOf.type = () => `{ [_:${getType(keyTypeFn)}]: ${getType(typeFn)} }`
    return mapOf
  }