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substr_replace()

Theory

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substr_replace()

If you can teach substr_replace() using Priya walking through substr_replace, you know it. If you only know the heading, you don’t.

substr_replace() order: meaning → one substr_replace step Priya can write from memory → one limit. Dumping ten features helps nobody.

Without substr_replace(), a small live site gets messy and Priya walking through substr_replace is hard to trust.

substr_replace() shows up in a small live site. Name Priya walking through substr_replace, not “a real-world scenario”.

Don’t do this with substr_replace(): copy-pasting substr_replace without a dry-run. Interviewers spot it in ten seconds.

After substr_replace(), Priya should still remember copy-pasting substr_replace without a dry-run.

Close substr_replace() with: “If I skip it, Priya walking through substr_replace goes wrong like this: copy-pasting substr_replace without a dry-run.”

Exam tip

Board: Priya walking through substr_replace. Dry-run substr_replace(). Name the trap: copy-pasting substr_replace without a dry-run.

Example

<?php
// substr_replace()
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

substr_replace(): scores array, print avg, then high marks. Say the output.

Short notes

Defsubstr_replace() — Priya uses it for Priya walking through substr_replace in a small live site.
Rulesubstr_replace() → one substr_replace step Priya can write from memory.
Remembersubstr_replace() + the PHP runtime (a small live site).
Usesubstr_replace() in a small live site (Priya walking through substr_replace).
Trapsubstr_replace() — copy-pasting substr_replace without a dry-run.
Exsubstr_replace() → Priya walking through substr_replace.

<?php // substr_replace() $scores = [80, 90, 70]; $avg = array_sum($scores) / count($scores); echo "avg=" . number_format($avg, 1) . "\n"; foreach ($scores as $s) { if ($s >= 80) echo "high: $s\n"; }

substr_replace()

Example

Short notes

Questions

substr_replace()

Example

Short notes

Questions