Example: classnames javascri+t Installation : yarn add classnames or npm i classnames Usage : classNames ( 'foo' , 'bar' ) ; // => 'foo bar' classNames ( 'foo' , { bar : true } ) ; // => 'foo bar' classNames ( { 'foo-bar' : true } ) ; // => 'foo-bar' classNames ( { 'foo-bar' : false } ) ; // => '' classNames ( { foo : true } , { bar : true } ) ; // => 'foo bar' classNames ( { foo : true , bar : true } ) ; // => 'foo bar' // lots of arguments of various types classNames ( 'foo' , { bar : true , duck : false } , 'baz' , { quux : true } ) ; // => 'foo bar baz quux' // other falsy values are just ignored classNames ( null , false , 'bar' , undefined , 0 , 1 , { baz : null } , '' ) ; // => 'bar 1' TypeInstallation : yarn add @types / classnames