Yep, I think my main problem was understanding what 'parse' meant.

Discussion below uses this code

our $initialised = 0;
BEGIN {
    _initialise();
    $initialised = 1;
}

[download]

Initially (when I didnt understand the problem) I thought the bare (not in a BEGIN) our $initialised = 0; meant 'found a scalar declaration, allocate memory, create an entry in the symbol table that references that location,and put a 0 in that memory location. Now parse and run the BEGIN block, which will result in $initialised having a 1 in it'.

Now I (think/know) it means 'found a scalar declaration, allocate memory, create an entry in the symbol table that references that location,and generate some opcodes that will result in a 0 being put in that location at runtime.Now parse and run the BEGIN block, which will result in $initialised having a 1 in it, which will get clobbered back to 0 by the opcodes at runtime'

Thanx merlyn for taking the time to break this down for me. I hope I have it straight now.

use brain;

In reply to Re^6: What can we assume in a BEGIN block ? by leriksen
in thread What can we assume in a BEGIN block ? by leriksen

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