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  Reading CONSTANTS versus Global Variables
Constants 0.0356 Globals x 1.22 faster 0.0291
  + vs += integer operators
+ integer 0.0471 += integer x 1.21 faster 0.0388
  + vs += string operators
+ strings 0.0814 += strings x 1.14 faster 0.0715
  += vs + string operators
+= strings x 1.19 faster 0.0734 + strings 0.0872
  short vs long variable names
short var name (1 char) x 1.44 faster 0.0206 long var name (72 chars) 0.0297

Testing PHP 4.0.6 Completed on Linux. Benchmark done on: 01-Mar-2004 09:08:09

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