Editing WoW:Making a macro (section)

===Empty parameters===

One source of confusion comes in dealing with parameterless commands. A very common error when writing macros is to add an extra semicolon to the end, but this creates some unexpected bugs. Take the following macro:

 /petattack [@focus, harm];

To the uninitiated, that looks like it'll send your pet after your focus if it's harmful, and do nothing otherwise. However, let's look at a breakdown of this macro:

 /petattack [@focus, harm]  ;
 \________/ \____________/ V V V
     |               |     | | |
  command         options  | | parameters (empty)
                           | |
                           | options (empty)
                           |
                           parameters (empty)

See that extra blank set of options and parameters? Remember that a blank set of options always evaluates to true, so that second empty parameter gets passed to /petattack if the first conditions are false.