mIRC is not considered a fast language and, more often than not, the easiest implementation is not the fastest.

The following tips will help to increase the execution speed of a script. Most will have a very marginal speed advantage and, as such, may not be worth the hassle outside of long-running script blocks such as loops.

Custom alias bypassing

When calling any form of command or identifer mIRC attempts to find a scripted version prior to looking for native functionality. This can be bypassed by prefixing commands with ! and by inserting a ~ after the $ of identifers

if-else vs $iif()

$iif() is much slower than using an if-else statement. When $iif() is evaluated it is first rearranged into an if-else statement and the resulting if-else statement is parsed.