Javascript call nested function

    function initValidation()
    {
        // irrelevant code here
        function validate(_block){
            console.log( "test", _block );
        }
    
        initValidation.validate = validate;
    }

    initValidation();
    initValidation.validate( "hello" );
    //test hello

Hope that you are looking for something like this

function initValidation()
{
    // irrelevant code here
    this.validate = function(_block){
        // code here
    }
}

var fCall = new initValidation()
fCall.validate(param);

This will work.

Hope this addresses your problem.