Shorthand conditionals like the ternary (? :) and null coalescing (??) operators are compact alternatives to if-else for value assignment; 2. The ?? operator is faster than isset() checks due to single opcode execution, while ternary performs similarly to if-else in simple cases; 3. They improve readability when used for simple conditions but reduce clarity when nested or used with complex logic; 4. Best practices include using ?? for null checks, limiting ternary to one level with short expressions, avoiding side effects, and preferring explicit blocks for complex or nested logic; 5. In templates, shorthand improves brevity without sacrificing clarity, making it ideal for simple output conditions.

PHP shorthand conditionals—like the ternary operator (? :) and the null coalescing operator (??)—are commonly used in modern PHP development. They offer a compact way to write simple conditional logic, but how do they stack up in terms of performance and readability? Let’s break it down.

1. What Are Shorthand Conditionals in PHP?

Shorthand conditionals are concise alternatives to full if-else statements when you're assigning a value based on a condition.

Ternary Operator (? :)

$result = $condition ? 'yes' : 'no';

Equivalent to:

if ($condition) {
    $result = 'yes';
} else {
    $result = 'no';
}

Null Coalescing Operator (??)

$username = $_GET['user'] ?? 'guest';

Only checks for null (not falsy values), equivalent to:

$username = isset($_GET['user']) ? $_GET['user'] : 'guest';

These are especially useful in assignments, function returns, and templating.

2. Performance: Are They Faster?

In most real-world cases, the performance difference is negligible—but let’s look under the hood.

Ternary vs. if-else

• The ternary operator compiles to similar opcodes as a basic if-else in PHP’s Zend Engine.
• Microbenchmarks show almost identical execution times for simple cases.
• However, nested ternaries can generate more complex opcode chains and may be slightly slower due to expression evaluation overhead.

Null Coalescing (??) vs. isset() + Ternary

• ?? is faster than isset($var) ? $var : 'default' because:
  • It’s a single opcode (ZEND_COALESCE) in PHP 7+.
  • It avoids function call overhead and redundant variable lookups.
• In PHP 8, this is even more optimized with better type handling.

? Verdict: ?? wins on performance for null checks. Ternary is on par with if-else for simple cases.

3. Readability: When to Use and When to Avoid

Clean, readable code matters more than micro-optimizations.

? Good Use Cases

• Simple assignments:

  $status = $active ? 'online' : 'offline';

• Default values with ??:

  $name = $user['name'] ?? 'Anonymous';

• Return statements:

  return $valid ? 200 : 400;

? Avoid These Patterns

• Nested ternaries:

  $result = $a ? 'A' : ($b ? 'B' : ($c ? 'C' : 'D'));

  Hard to read. Use if-elseif-else instead.

• Complex logic in shorthand:

  $output = $user && $user->isActive() && !$user->isBanned() ? generateReport($user) : null;

  Too dense. Break it into a proper block.

• Side effects inside ternary:

  $result = $cond ? doSomething() : doSomethingElse();

  While valid, it can obscure flow. Better to be explicit.

4. Best Practices for Using Shorthand Conditionals

Stick to these guidelines to keep your code fast and maintainable:

• ? Use ?? for null checks—it's cleaner and faster.
• ? Use ternary only for simple, one-level conditions with short expressions.
• ? Keep both branches of a ternary on one line if they fit (improves scanability).
• ? Avoid nesting more than one level.
• ? Don’t use shorthand for statements with side effects (e.g., function calls that change state).
• ? In templates (like PHP in HTML), shorthand improves brevity:

  <div class="status <?= $active ? 'active' : 'inactive' ?>">

  ---

  Final Thoughts

  Shorthand conditionals are powerful tools when used appropriately. The ?? operator is both faster and clearer than isset() checks. The ternary operator saves space and is fine for simple logic—but readability should trump brevity.

  Basically:
  Use ?? freely.
  Use ? : sparingly.
  And never sacrifice clarity for cleverness.

  That’s the real performance win.

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