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Date: Sun, 01 Apr 2012 14:19:22 +0200
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Subject: Question about parser implementation details
From: ml@anderiasch.de (Florian Anderiasch)

Hey there,
due to the widespread acceptance of binary number format (0b1010101) and
the growing demand for backwards compatibility I've started to work on
support for Roman Numerals (I, II, III, ...)

As you might know, this format cannot be strictly parsed from left to
right or right to left, as several number values need a look-ahead
before being able to compute them (like IV), so my naive first
implementation splits the string into tokens (like in 1990 = MCMXC =>
M,CM,XC => 1000,900,90) then simplifying those 3 on their own, then
adding the results, but I'm not sure this could kill performance if
calculated inside zend_language_scanner.l.

I'd appreciate any hints on how to tackle this serious concern.

Btw, in the spirit of x for hex and b for binary I thought about using
this syntax:

<?php
$a = 0spqrMMXII; //set $a to 2012
?>

unless anyone has any better suggestions?

Greetings,
Florian