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<?php // Curious about the bytecode difference between comma-separated and period-concatenated echoes echo 'foo', 'bar', 'baz'; echo 'foo' . 'bar' . 'baz'; echo 'foo', 'bar'[rand(0,2)], 'baz';
Output for 5.5.0 - 5.5.1, 5.5.3, 5.5.8 - 5.5.9, 5.5.11, 5.5.13, 5.5.16, 5.5.23, 5.5.28, 5.5.30, 5.5.32, 5.5.35, 5.6.5, 5.6.9 - 5.6.11, 5.6.13, 5.6.23 - 5.6.24, 5.6.29 - 5.6.30, 5.6.33 - 5.6.35, 5.6.38, 7.0.1 - 7.0.2, 7.0.8 - 7.0.9, 7.0.12, 7.0.23, 7.0.26, 7.0.28, 7.1.3, 7.1.14, 7.1.16, 7.1.25, 7.1.28, 7.2.1, 7.2.3, 7.2.5, 7.2.9, 7.2.11, 7.2.16 - 7.2.17, 7.2.19, 7.2.21, 7.3.2 - 7.3.3, 7.3.5 - 7.3.6, 7.3.8, 7.3.12
foobarbazfoobarbazfoorbaz
Output for 5.5.2, 5.5.4, 5.5.6, 5.5.21, 5.5.25 - 5.5.27, 5.5.33, 5.6.0 - 5.6.1, 5.6.6 - 5.6.8, 5.6.12, 5.6.14, 5.6.17 - 5.6.20, 5.6.27, 5.6.32, 5.6.36 - 5.6.37, 7.0.0, 7.0.6 - 7.0.7, 7.0.11, 7.0.13, 7.0.16, 7.0.19 - 7.0.21, 7.0.31 - 7.0.32, 7.1.0, 7.1.4, 7.1.7 - 7.1.8, 7.1.11 - 7.1.13, 7.1.17, 7.1.20 - 7.1.21, 7.1.26 - 7.1.27, 7.1.29 - 7.1.32, 7.2.0, 7.2.2, 7.2.4, 7.2.6, 7.2.13, 7.2.20, 7.2.22 - 7.2.24, 7.3.0 - 7.3.1, 7.3.4, 7.3.10 - 7.3.11
foobarbazfoobarbazfoobbaz
Output for 5.5.5, 5.5.7, 5.5.10, 5.5.12, 5.5.14 - 5.5.15, 5.5.17 - 5.5.20, 5.5.22, 5.5.24, 5.5.29, 5.5.31, 5.5.34, 5.5.36 - 5.5.38, 5.6.2 - 5.6.4, 5.6.15 - 5.6.16, 5.6.21 - 5.6.22, 5.6.25 - 5.6.26, 5.6.28, 5.6.31, 7.0.3 - 7.0.5, 7.0.10, 7.0.14 - 7.0.15, 7.0.17 - 7.0.18, 7.0.22, 7.0.24 - 7.0.25, 7.0.27, 7.0.29 - 7.0.30, 7.0.33, 7.1.1 - 7.1.2, 7.1.5 - 7.1.6, 7.1.9 - 7.1.10, 7.1.15, 7.1.18 - 7.1.19, 7.1.22 - 7.1.24, 7.1.33, 7.2.7 - 7.2.8, 7.2.10, 7.2.12, 7.2.14 - 7.2.15, 7.2.18, 7.3.7, 7.3.9
foobarbazfoobarbazfooabaz
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45
Parse error: syntax error, unexpected '[', expecting ',' or ';' in /in/iVDtG on line 9
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[', expecting ',' or ';' in /in/iVDtG on line 9
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `','' or `';'' in /in/iVDtG on line 9
Process exited with code 255.

preferences:
207.86 ms | 401 KiB | 318 Q