Create Print() function

[jasonwilliams]

Arises from:
jasonwilliams#74

1. `print()` function in the global scope (or similar). SpiderMonkey's JavaScript shell defines this as: 
    > Evaluates the expression(s) and displays the result(s) on `stdout`, separated by spaces (" ") and terminated by a newline ("\n").

For Boa Shell we need a print function, the implementation is virtually the same as https://github.com/jasonwilliams/boa/blob/master/src/lib/js/console.rs#L11-L98

It might be worth abstracting the above logic into its own function, and have console.log() and print() use it.

print() should only be available in shell

So you will need to add it to the realm there.
You may need to create a helper function in realm which lets you add Objects to the global scope.

Spidermonkey equivalent

https://github.com/mozilla/gecko-dev/blob/master/js/src/shell/js.cpp#L2687-L2724

[Emanon42]

Interest in this. Can I take a try?

[jasonwilliams]

Sure!

[jasonwilliams]

In terms of the helper, there exists one in the spec:
https://tc39.es/ecma262/#sec-getglobalobject

The Execution context should have a getRealmObject method.
It might be worth returning a reference to the realm object for now.

You will need this to add Print to the global object before running

[louiidev]

if you call print() in the browser(chrome) it opens the printer prompt

[jasonwilliams]

@louisgjphnson this method won’t be in the final binary, only in the shell

[IovoslavIovchev]

@Emanon42 note that what we need is close to some of the work done in #171, so you can take a look (specifically having Display, console.log and print share some logic).

[Emanon42]

@IovoslavIovchev @jasonwilliams thanks! I have to delay my contribution on this issue because of my uni coursework :p
I will finish this before December!

[IovoslavIovchev]

@Emanon42 no worries, take your time