everyOwnBy

Test whether all own propertes of an object pass a test implemented by a predicate function.

Usage

var everyOwnBy = require( '@stdlib/utils/every-own-by' );

everyOwnBy( object, predicate[, thisArg ] )

Tests whether all own properties of an object pass a test implemented by a predicate function.

function isPositive( value ) {
    return ( value > 0 );
}

var obj = {
    'a': 1,
    'b': 2,
    'c': 3,
    'd': 4
};

var bool = everyOwnBy( obj, isPositive );
// returns true

If a predicate function returns a non-truthy value, the function immediately returns false.

function isPositive( value ) {
    return ( value > 0 );
}

var obj = {
    'a': 1,
    'b': -2,
    'c': 3,
    'd': 4
};

var bool = everyOwnBy( obj, isPositive );
// returns false

The invoked function is provided three arguments:

value: property value.
key: property key.
obj: input object.

To set the function execution context, provide a thisArg.

function sum( value ) {
    if ( value < 0 ) {
        return false;
    }
    this.sum += value;
    this.count += 1;
    return true;
}

var obj = {
    'a': 1,
    'b': 2,
    'c': 3
};

var context = {
    'sum': 0,
    'count': 0
};

var bool = everyOwnBy( obj, sum, context );
// returns true

var mean = context.sum / context.count;
// returns 2

Notes

If the 1st argument is not an object or the second argument is not a fuction , the function throws a Type Error.

If provided an empty object, the function returns true.

function untrue() {
    return false;
}
var bool = everyOwnBy( {}, untrue );
// returns true

Examples

var randu = require( '@stdlib/random/base/randu' );
var everyOwnBy = require( '@stdlib/utils/every-own-by' );

function isPositive( value ) {
    return ( value > 0 );
}

var obj = {};
var i;

// Populate object with random values
for ( i = 0; i < 100; i++ ) {
    obj[ 'prop_' + i ] = randu();
}

var bool = everyOwnBy( obj, isPositive );
// returns <boolean>