Old habits dye hard, or at least dark grey.
Coming from a 'C'/C++ background, I hate to constantly access an array element in a loop using the array subscripting. I prefer a pointer to the entry after computing subscripts once.
With a hash, is it better to take a reference to the the keyed scalar, or repeatedly recompute the hash?
A snippit of a 60 line loop
ELEMENT:
foreach $key (keys %Contracts)
{
$tot_count++;
{# lock block
lock @{$Contracts{$key}};
next ELEMENT if ($Contracts{$key}[STATE] eq $ST_VOID);
next ELEMENT if ($Contracts{$key}[STATE] eq $ST_REPORTED
+);
$elapsed_time = time() - $Contracts{$key}[START];
.... lots more accesses to the $Contracts{$key} record.
Does 'locality or reference' optimized that hash access, or is the key rehashed on every use in the loop?
?Better?
ELEMENT:
foreach $key (keys %Contracts)
{
$tot_count++;
{# lock block
lock @{$Contracts{$key}};
$Cntrct_ref = \$Contracts{$key};
next ELEMENT if ($Cntrct_ref[STATE] eq $ST_VOID);
next ELEMENT if ($Cntrct_ref[STATE] eq $ST_REPORTED);
$elapsed_time = time() - $Cntrct_ref[START];
...
Wisdom is needed, please
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