does an element have an attribute

hasAttr.js

// has

const hasAttr = ( _el, attr ) => {

	if ( ! 'children' in _el || _el.children[ 0 ] ) {
		return false;
	}
	
	if ( _el.nodeType !== 1) {
		return false;
	}

	if ( ! typeof attr === 'string' ) {
		return false;
	}

	let res = {
		att: false,
		value: ''
	}

	const writeObj = function ( values ) {
		
		let cache = new WeakMap();
		let val = '';

		for ( key, value in values ) {
			val = defineObjValue( key, {
				value: value
			} ).call( res )
		}

		return cache.add( 'key', val );

	}

	const defineObjValue = function( key, writeObj ) {
		// single use principle makes for more streamlined write api's
		if ( ! writeObj.writeable ) {
			writeObj.writeable = true;
		}

		Object.defineProperty( this, key, writeObj )

		return this

	}.bind(res)

	/**************************
	 * what does this api look like
	 * 
	 *  writeObj({
	 *  	att: 'class',
	 *  	value: 'classList classListModifier className'
	 *  })
	 *
	 *  alternative tree structure
	 *  writeObj(['att', 'class', 'value', 'className'])
	 * 
	 */

	// order of precedence
	// micro-optimizations would select attribute types that are used first
	
	if ( _el[ attr ] ) {

		if ( Array.isArray( _el[ attr ] ) ) {
			// if 0 index is undefined
		}

		if (typeof _el[ attr ] === 'object' ) {
			// if hasOwnProperty count === 0
			
			/*************************************************
			 * First implementation 
			 * 
			 */
			
			let ownPropertyCount = 0;

			// technically within the same block
			for (key, prop in obj) {
				 obj.hasOwnProperty(prop) ?? ++ownPropertyCount;
			}

			if ( ownPropertyCount > 0 ) {
				return true;
			}

			/*************************************************
			 * Alternative implementation
			 * - this is the more standard approach
			 */
			for (key, prop in obj) {
				if ( obj.hasOwnProperty(prop) ) {
					return true;
				}
			}
		}
		// @todo optional chaining
		if (typeof _el[ attr ] === 'string' ) {
			if ( _el[ attr ] === undefined ||
				_el[ attr ] === '' ) {
				return true;
			}
		}

		return true;
	}

	if ( _el.data[ attr ] ) {
		return writeObj.call(res, 'attr', _el.data[ attr ])
	}

	for ( let i = 0; i < el.children; i++ ) {
		if ( el.children[ i ][ attr ] ) {
			return {
				child: true;
			}
		}
	}

	//for ( let i = 0; i < el. )
}

module.exports = hasAttr

better error handling, better designed object handling and object cache, more micro ops, better attention to detail, dev ops integration

robust web api integration

data attribute event api

TODO