bind.js

function bind(fn, context) {
    var givenArguments = [];
    
    for (var _i = 2; _i < arguments.length; _i++) {
        givenArguments[_i - 2] = arguments[_i];
    }
    
    if (typeof Function.prototype.bind == "function") {
        return Function.prototype.bind.apply(fn, Array.prototype.concat.apply([context], givenArguments));
    }
    
    return (givenArguments.length > 0)
        ? function () {
            var localArguments = [];
            
            for (var _i = 0; _i < arguments.length; _i++) {
                localArguments[_i - 0] = arguments[_i];
            }
            
            return (localArguments.length > 0)
                ? fn.apply(context, Array.prototype.concat.apply(givenArguments, localArguments))
                : fn.apply(context, givenArguments);
        }
        : function () {
            var localArguments = [];
            
            for (var _i = 0; _i < arguments.length; _i++) {
                localArguments[_i - 0] = arguments[_i];
            }
            
            return (localArguments.length > 0)
                ? fn.apply(context, localArguments)
                : fn.apply(context);
        };
}

bind.ts

function bind(fn: Function, context: Object, ...givenArguments: Array<any>): Function {
    if (typeof Function.prototype.bind == "function") {
        return Function.prototype.bind.apply(fn, Array.prototype.concat.apply([context], givenArguments));
    }
    
    return (givenArguments.length > 0)
        ? (...localArguments: Array<any>) => {
            return (localArguments.length > 0)
                ? fn.apply(context, Array.prototype.concat.apply(givenArguments, localArguments))
                : fn.apply(context, givenArguments)
        }
        : (...localArguments: Array<any>) => {
            return (localArguments.length > 0)
                ? fn.apply(context, localArguments)
                : fn.apply(context)
        };
}