MT4 EA recompiling - effect on running EA

[gt21]

Hi, newbie question: If I have an EA attached and running on chart A, then I tweaked the code, recompiled and attach it on chart B, will it affect EA on chart A?

[Ubzen]

https://docs.mql4.com/check/UninitializeReason

It'll probably uninit and reinit [case REASON_RECOMPILE]. As for affecting your trading logic and variables, it depends on how the Expert is coded.

[William Roeder]

Definitely unInit, EA reloaded (meaning all global and static variables have been reset), init called. Only in the tester does compiling not reload the EA.

[gt21]

But EA running on different charts have completely separate scope and global variables right?

[Simon Gniadkowski]

gt21:
Hi, newbie question: If I have an EA attached and running on chart A, then I tweaked the code, recompiled and attach it on chart B, will it affect EA on chart A?

Where was the mq4 file when you recompiled it ?  I keep all my source code in a series of directories unrelated to any of my MT4 installations . . .  I can tweak and recompile till I'm blue in thee face and this has no effect on any of my terminals . . .

 

gt21:
But EA running on different charts have completely separate scope and global variables right?

Yes.