Javascript: what does this syntax mean (0,functionName)(functionParemeter); -

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i wondering javascript file source of http://www.google.com , try understand have done there. today wondering inside files , found strange function calls. maybe silly thing have no idea , couldn't searching it.

a readable resemble of code-

var somefunction = function(somaeparamenter){     //do stuffs;     return something; }  var someotherthing = (0, somefunction)(oneparameter);

please excuse lack of knowledge.

edit:

source-

i'm using chrome. while in http://www.google.com page open, opened developer tool. opened sources tab , opened file https://www.google.com.bd/xjs/_/js/s/c,sb,cr,cdos,vm,tbui,mb,wobnm,cfm,abd,bihu,kp,lu,m,tnv,amcl,erh,hv,lc,ob,r,rsn,sf,sfa,shb,srl,tbpr,hsm,j,p,pcc,csi/rt=j/ver=wuw4ydif-wi.en_us./am=ga/d=1/sv=1/rs=aitrstpu52cumknqsh0was81vrm4inla_w in viewer. file js file i've seen there. enabled "pretty print" , in line 58 you'll find defination-

_.va = function(a) {             var b = typeof a;             if ("object" == b)                 if (a) {                     if (a instanceof window.array)                         return "array";                     if (a instanceof window.object)                         return b;                     var c = window.object.prototype.tostring.call(a);                     if ("[object window]" == c)                         return "object";                     if ("[object array]" == c || "number" == typeof a.length && "undefined" != typeof a.splice && "undefined" != typeof a.propertyisenumerable && !a.propertyisenumerable("splice"))                         return "array";                     if ("[object function]" == c || "undefined" != typeof a.call && "undefined" != typeof a.propertyisenumerable && !a.propertyisenumerable("call"))                         return "function"                 } else                     return "null";             else if ("function" == b && "undefined" == typeof a.call)                 return "object";             return b         };

and in line 83 you'll see function called.

_.za = function(a) {             return "array" == (0, _.va)(a)         }; 

(0, somefunction)

simply returns somefunction

so equivalent to

var someotherthing = somefunction(oneparameter);

are sure typed ? if so, , if wasn't kind of obfuscation, might unfortunate result of minification. if real code little different, example (0, someobject.somefunction) , there might use of indirect function call.

edit :

you edit confirms goal ensure this, inside function, global object (window in browser) , not object on va attached (_).


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