Module function/cond

cond

• cond<T, F>(fns: ArrayLike<[Pred<T>, F]>): (...args: T[]) => ReturnType<F>

• Returns a function, fn, which encapsulates if/else-if/else logic. cond takes a list of [predicate, transform] pairs. All of the arguments to fn are applied to each of the predicates in turn until one returns a "truthy" value, at which point fn returns the result of applying its arguments to the corresponding transformer. If none of the predicates matches, fn returns undefined.

  example

   var fn = cond([
     [isEqual(0),   always('water freezes at 0°C')],
     [isEqual(100), always('water boils at 100°C')],
     [T,           temp => 'nothing special happens at ' + temp + '°C']
   ]);
   fn(0); //=> 'water freezes at 0°C'
   fn(50); //=> 'nothing special happens at 50°C'
   fn(100); //=> 'water boils at 100°C'
  

  Type parameters

  • T

  • F: (...args: any[]) => any

  Parameters

  • fns: ArrayLike<[Pred<T>, F]>

  Returns (...args: T[]) => ReturnType<F>

  • • (...args: T[]): ReturnType<F>

    • Parameters

      • Rest ...args: T[]

      Returns ReturnType<F>