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Magic Constants

Theory

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Magic Constants

Magic Constants is simple if you keep it on paper. Amit uses it for Amit walking through Magic Constants in lab hour.

Do Magic Constants once by hand. one Magic Constants step Amit can write from memory. Change one input. Say the new result out loud.

Magic Constants exists so Amit can keep Amit walking through Magic Constants correct in lab hour.

Magic Constants shows up in lab hour. Name Amit walking through Magic Constants, not “a real-world scenario”.

If Amit walking through Magic Constants breaks under Magic Constants, check skipping the failure case for Magic Constants first.

After Magic Constants, Amit should still remember skipping the failure case for Magic Constants.

One breath for Magic Constants, then Amit walking through Magic Constants, then skipping the failure case for Magic Constants. Sit down.

Exam tip

Board: Amit walking through Magic Constants. Dry-run Magic Constants. Name the trap: skipping the failure case for Magic Constants.

Example

<?php
// Magic Constants
$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";
}

Magic Constants: scores array, print avg, then high marks. Say the output.

Short notes

DefMagic Constants — Amit uses it for Amit walking through Magic Constants in lab hour.
RuleMagic Constants → one Magic Constants step Amit can write from memory.
RememberMagic Constants + Apache/Nginx (lab hour).
UseMagic Constants in lab hour (Amit walking through Magic Constants).
TrapMagic Constants — skipping the failure case for Magic Constants.
ExMagic Constants → Amit walking through Magic Constants.

<?php // Magic Constants $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"; }

Magic Constants

Example

Short notes

Questions

Magic Constants

Example

Short notes

Questions