Re^2: perl compiler optimizer curiosity

unfortunately there is no macro mechanism in pure Perl.

Technically, there is. Although using source code filters is not a good idea, it's basically a smarter version of C makros.

perl -e 'use Crypt::Digest::SHA256 qw[sha256_hex]; print substr(sha256_hex("the Answer To Life, The Universe And Everything"), 6, 2), "\n";'

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Re^3: perl compiler optimizer curiosity by LanX (Saint) on Mar 15, 2022 at 11:50 UTC
Sorry, if I say "macro" I mean real ones like in Lisp. Preprocessor macros like in C are sh*t in comparison. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
[OT] Re^4: perl compiler optimizer curiosity by afoken (Chancellor) on Mar 15, 2022 at 11:58 UTC
if I say "macro" I mean real ones like in Lisp. Preprocessor macros like in C are sh*t in comparison. I never used Lisp, but I know C. Can you show some examples? Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply]
Re^5: perl compiler optimizer curiosity (syntactic macros) by LanX (Saint) on Mar 15, 2022 at 12:16 UTC
We had this discussion multiple times before, but I can't find those threads in a hurry. Preprocessing/source filter means you have an second parsing stage which has not only to reproduce the whole syntax (horror in Perl) but might also expand to unpredictable results when combined (like two source filters) Lisp'ish Syntactic macros: look and parse like functions the arguments are used as building blocks for an "expanded" template the expansion happen while compiling in the same stage don't require any syntax parsing by themselves can be used to efficiently extend syntax There are still some traps, like the need for "hygiene", but this a problem with dumber source filters too. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery} update see also https://en.wikipedia.org/wiki/Macro_(computer_science)#Syntactic_macros	[reply]

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