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POExecute Code Segment only if Loop reaches its last cycle (End of Loop)
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copied!<p>Where is the most efficient position for a code block, which shall only execute, if a loop has reached its end, without having previously been aborted (via break or return)?</p> <p>The question seems banal, the answer obvious, nevertheless I am insecure!</p> <p>Answer from efficiency/theory professionals very welcome!</p> <hr> <ol> <li><p><strong>Provided</strong>: "Some Code X" is always the same, only at different Code Segment Positions 1 and 2.</p></li> <li><p><strong>I assume</strong>: 2 will be executed with the same reliability as 1. Am I wrong?</p></li> <li><p><strong>I know:</strong> 2 is obviously more efficient, as it is only called once after the loop ran $limit times, compared to 1, whose enclosing if-condition is called $limit times, and if once true, the code itself is called. Thus the <strong>efficiency difference</strong> is <strong>if-condition queried $limit times</strong>.</p></li> </ol> <p>Hence I conclude: To prefer using Code Segment 2 rather than Code Segment 1, unless my assumption is wrong!</p> <hr> <pre><code>for ($i = 0; $i <= $limit; $i++) { // Some Code A [...] // Executed every iteration. // If condition is met, abort the loop and return $result if (condition) { return $result; } // Code Segment 1, only executed in last iteration if no abortion happened previously. If-condition checked $limit times! if ($i == $limit) { // Some Code X [...] return $result } } // Code Segment 2, only executed if no abortion happened. At most executed only once! // Some Code X [...] return $result </code></pre>

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