How to check if argument is defined in function definition in JavaScript? -


for example if have function defined this:

function set_name(name) {     return name; }

but call way (for personal reasons way):

set_name.apply(this, ['duvdevan', 'omerowitz']);

what best practice check , prevent set_name function's further execution if had accepted more 1 parameter / argument?

also, have note i'm trying figure out way check before call .apply function:

function set_name(name) {     // if(arguments.length > 1) console.log('this not need though.');      return name; }  var args = ['duvdevan', 'omerowitz'];  // now, @ point i'd check if set_name function can accept 2 arguments. // if not, i'd console.log or return new error here.  set_name.apply(this, args);

is doable?

you can number of arguments expected function via function.length:

function set_name(name) {    return name;  }    var args = ['duvdevan', 'omerowitz'];    console.log(set_name.length);         // 1    if (args.length > set_name.length) {    throw new error('too many values'); // throws  }    set_name.apply(this, args);           // not executed


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