60 lines
1.5 KiB
Plaintext
60 lines
1.5 KiB
Plaintext
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{{alias}}( predicate, x, y, done )
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If a predicate function returns a truthy value, returns `x`; otherwise,
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returns `y`.
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A predicate function is provided a single argument:
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- clbk: callback to invoke upon predicate completion
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The callback function accepts two arguments:
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- error: error object
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- bool: condition used to determine whether to invoke `x` or `y`
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The `done` callback is invoked upon function completion and is provided at
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most two arguments:
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- error: error object
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- result: either `x` or `y`
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Execution is *not* guaranteed to be asynchronous. To guarantee asynchrony,
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wrap the `done` callback in a function which either executes at the end of
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the current stack (e.g., `nextTick`) or during a subsequent turn of the
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event loop (e.g., `setImmediate`, `setTimeout`).
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Parameters
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----------
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predicate: Function
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Predicate function.
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x: any
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Value to return if a condition is truthy.
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y: any
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Value to return if a condition is falsy.
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done: Function
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Callback to invoke upon completion.
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Examples
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--------
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> function predicate( clbk ) {
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... setTimeout( onTimeout, 0 );
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... function onTimeout() {
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... clbk( null, true );
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... }
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... };
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> function done( error, result ) {
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... if ( error ) {
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... throw error;
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... }
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... console.log( result );
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... };
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> {{alias}}( predicate, 'beep', 'boop', done )
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'beep'
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See Also
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--------
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