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Underscore is a JavaScript library that provides a lot of useful functional helpers without extending any built-in objects.
Question: How to install async module?
npm install underscore
Question: How to include request module in node project?
var _ = require("underscore");
Question: Give an example of each in underscore?
_.each(['Understand', 'underscore', 'Module'], function(value,pos){
console.log(value+' stored at '+pos);
});
Output
Understand stored at 0 underscore stored at 1 Module stored at 2
Question: What are other collections in underscore module?
each map reduce reduceRight find filter where findWhere reject every some contains invoke pluck max min sortBy groupBy indexBy countBy shuffle sample toArray size partition
Question: How to create a range array?
var lists=_.range(5); console.log(_.first());
Question: How to get first nth element from array?
var lists=["One","two","three","four", "five"]; console.log(_.first(lists)); //One console.log(_.first(lists,2)); //One two console.log(_.first(lists,3)); //One two three
Question: How to check a variable is empty OR Not ?
var name='' console.log(_.isEmpty(name));//true name='Hello User' console.log(_.isEmpty(name));//false
Question: What are array functions in underscore module?
first initial last rest compact flatten without union intersection difference uniq zip unzip object indexOf lastIndexOf sortedIndex findIndex findLastIndex range
Question: How to get key value of an object data?
var lists={1:"One",2:"two",3:"three",4:"four", 5:"five"};
console.log(_.keys(lists)); //1,2,3,4,5
Question: What are the object functions in underscore module?
keys allKeys values mapObject pairs invert create functions findKey extend extendOwn pick omit defaults clone tap has matcher property propertyOf isEqual isMatch isEmpty isElement isArray isObject isArguments isFunction isString isNumber isFinite isBoolean isDate isRegExp isError isNaN isNull isUndefined
