Extern 1

In my last article about improved input settings in mql4 I told you about enumerations and how they allow you to utilize drop down menus in your EA's settings. That was certainly a great improvement to the way settings are handled in MQL4 but there's another feature that you should be using.

If you're familiar with the original style of MQL4 coding you've probably used 'extern' variables to facilitate input from users. Since build 600 of MetaTrader 4 there's a new kid on the block.

Input variables or settings can now be declared as either 'extern' or 'input' and the difference between the two is pretty straight forward. (more…)