note 50082 added to language.types.float

From: Date: Thu, 17 Feb 2005 12:31:01 +0000
Subject: note 50082 added to language.types.float
Groups: php.notes 
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The formal specification of the floating point numbers as specified above is not complete. For one thing, it is not immediately obvious which of the three rules describes "floating point numbers" (in general). The disjunction of all three perhaps? My interpretation is that a floating point number is either a DNUM or an EXPONENT_DNUM. Moreover, the specification as stated does not allow for signs (+ or -). Yet, PHP does actually allow for signs in the specification of floating point numbers (as one would expect): <?php $f = (float) "-0.5"; var_dump($f); // outputs "float(-0.5)" ?> Thus, the following specification is more complete: FLOAT [+-]?({DNUM}|{EXPONENT_DNUM}) LNUM [0-9]+ DNUM ([0-9]*[\.]{LNUM}) | ({LNUM}[\.][0-9]*) EXPONENT_DNUM ( ({LNUM} | {DNUM}) [eE][+-]? {LNUM}) ---- Manual Page -- http://www.php.net/manual/en/language.types.float.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+50082 Delete: added to the manual -- http://master.php.net/manage/user-notes.php?action=delete+50082&report=yes&reason=added+to+the+manual Delete: bad code -- http://master.php.net/manage/user-notes.php?action=delete+50082&report=yes&reason=bad+code Delete: spam -- http://master.php.net/manage/user-notes.php?action=delete+50082&report=yes&reason=spam Delete: useless -- http://master.php.net/manage/user-notes.php?action=delete+50082&report=yes&reason=useless Delete: other reasons -- http://master.php.net/manage/user-notes.php?action=delete+50082&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+50082&report=yes Search -- http://master.php.net/manage/user-notes.php

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