MQL5 EA run in MT4?

Quick question:

You know how MQL5 is going to be released before MT5. Was it mentioned whether EA's compiled in MQL5 can be run in MT4?

MQL5 is not backwards compatible with MT4 and I think the same is the other way round.

You mean MQL5 isn't compatible with MT4? (just to clarify, because you said MT5 and MT4, not MQL)

Yeah, that's what I wanted to say.

they have claimed that mt5 will down support mt4 and their ea. longing to try mt5 here.

NO,both the programming language and platform will not be backward compatible with MQL4 & MT4.And it's a BAD news!!

I actually think MQL5 will be pretty awesome, from what I heard from the interview. Finally, structures, and did I hear something about better debugging? And 5x execution speed. Nice!

Not the programming side of it...

MQL5 is OOP, that is very similar to C++. MQL4 is not.

So no compatibility forwards or backwards...

Yes originally they claimed backward compatability. But now they have changed their minds, and MT4 EA's will need to be modified.

The programming language should be the least of your worries.

The MT5 programming language has some C++ OO attributes, but that alone wouldn't necessarily make MQ4 code incompatible with MT5, since C code is forwards compatible with C++.

The main reason for incompatibility is that position management is going to be completely different. As I understand it, open positions maintained by MT5 will reflect the total position for that pair, and it will not be possible to have a simultaneous long and short trade with the broker, such what happens now with a long term EA running with a scalper.

This change in position management approach may need to happen now anyway even in MT4, with the FIFO rules against hedging introduced in the US.

The MT5 approach doesn't stop the practice of maintaining opposite positions, but it means that position management code will need to maintain "virtual positions" in the EA.

There is a bit of confusion here in this post I think.

MQL4 applications will not be compatible because of the way MT5 handles orders (you can only add to or remove from a position with MT5, you cannot create multiple orders on any single pair)

FIFO and No Hedging are NOT an American thing, only brokers that are regulated by the NFA will be required to abide by the FIFO and No Hedging rule, Any other brokers not regulated by the NFA are immune to this in my honest opinion, de-evolving step to the forex trading community.

The link below takes you to some MT4 scripts that help you convert your MQ4 code to MQ5 code. Nowhere near perfect but it is a start.

HERE IS THE LINK (posts 28 and 29)

Hi Paul,

I've just found your VOM and took a look at it. Very nice piece of code.
I'm interested in a similar library for MT4, for the purpose of overcoming the StopLevel burden. Also, I would like the VOM collect useful statistic on pending, running and closed trades to allow for fancier MM and stop strategies. Obviously, it would be very cumbersome to downgrade your code to mql4. Are you familiar with any existing mql4 code snippets doing that or partially doing it?

Thanks,

Trendick