here are the details:

i have four different machines (all linux, all i686). two of them are running perl 5.6.0, the other two 5.005.

i run the following test on all machines:

perl -e 'print("0x30"+0,"\n")'

here are the results:

first machine (5.6.0): 1.5
second machine (5.6.0): 48
third machine (5.005): 48
fourth machine (5.005): 1.5

the second and third machine always evaluate the expression to whatever the decimal value of the hex number in the string is. the first and fourh evaluate to a fractional number.

here is a test script i ran on one of the 'fractional' machines: 

#!/usr/bin/perl

for ($i=1; $i<64; $i++) {
  print(sprintf("%02X: ",$i),("0x".sprintf("%X",$i))+0,"\n");
}

[download]

here is the output: 

01: 1
02: 1
03: 1.5
04: 1
05: 1.25
06: 1.5
07: 1.75
08: 1
09: 1.125
0A: 1.25
0B: 1.375
0C: 1.5
0D: 1.625
0E: 1.75
0F: 1.875
10: 1
11: 1.0625
12: 1.125
13: 1.1875
14: 1.25
15: 1.3125
16: 1.375
17: 1.4375
18: 1.5
19: 1.5625
1A: 1.625
1B: 1.6875
1C: 1.75
1D: 1.8125
1E: 1.875
1F: 1.9375
20: 1
21: 1.03125
22: 1.0625
23: 1.09375
24: 1.125
25: 1.15625
26: 1.1875
27: 1.21875
28: 1.25
29: 1.28125
2A: 1.3125
2B: 1.34375
2C: 1.375
2D: 1.40625
2E: 1.4375
2F: 1.46875
30: 1.5
31: 1.53125
32: 1.5625
33: 1.59375
34: 1.625
35: 1.65625
36: 1.6875
37: 1.71875
38: 1.75
39: 1.78125
3A: 1.8125
3B: 1.84375
3C: 1.875
3D: 1.90625
3E: 1.9375
3F: 1.96875

[download]

now what i need is an explanation :)

In reply to Re: Why are hex numbers inside strings extrapolating to numbers (incorrectly)? by lanzz
in thread Why are hex numbers inside strings extrapolating to numbers (incorrectly)? by Anonymous Monk

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