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  Reading CONSTANTS versus Global Variables
Constants x 1.67 faster 0.0006 Globals 0.0010
  + vs += integer operators
+ integer 0.0007 += integer 0.0007
  + vs += string operators
+ strings 0.0017 += strings 0.0017
  += vs + string operators
+= strings 0.0016 + strings 0.0016
  short vs long variable names
short var name (1 char) x 5.50 faster 0.0002 long var name (72 chars) 0.0011

Testing PHP 4.3.3 Completed on WINNT. Benchmark done on: 29-Feb-2004 15:21:29

(c) 2003-2004 John Lim PHP Benchmark Suite (PHP BS 1.0).