They are executed in order of appearance, with the additional requirement that modules that are 'used' appear when the compiler passes by, and modules that are 'required' appear during run time.

So, if the script has "use A;" before "use B;", the compiler will complile "A" first (and during that compilation, it will compile any 'used' modules in A), then, when it has compiled A, it will compile B.

If 2 modules have dependencies on each other an they both do some initialization before defining subs, how can your guarantee which order the initialization code is run in?
It would be a lot easier if you don't have circular dependencies. One day, you, or someone coming after you, will change the code that requires A to be compiled before B, while at the same time, it requires B to be compiled before A.

Anyway, you will have to use BEGIN and INIT blocks, remembering that 'use' is a BEGIN block as well. BEGIN blocks are executed as soon as they are compiled. INIT blocks are run before the main program starts, and they are run in the order they are compiled in.

Perl --((8:>*

In reply to Re: Understanding order of module compilation and execution by Perl Mouse
in thread Understanding order of module compilation and execution by Anonymous Monk

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