Gettype and typeof checks in PHP - Step-by-Step Execution

Concept Flow - Gettype and typeof checks

Start

↓

Variable defined

↓

Use gettype()

↓

Output type as string

↓

Use get_debug_type() (PHP 8.0+)

↓

Output type as string

↓

End

The program defines a variable, then uses gettype() and get_debug_type() to check and output its type as a string.

Execution Sample

PHP

<?php
$var = 123;
echo gettype($var) . "\n";
echo get_debug_type($var) . "\n";
?>

This code sets a variable to 123, then prints its type using gettype() and get_debug_type().

Execution Table

Step	Action	Variable	Function Called	Result	Output
1	Define variable	$var	N/A	123 (integer)	N/A
2	Call gettype()	$var	gettype($var)	"integer"	integer
3	Call get_debug_type()	$var	get_debug_type($var)	"int"	int
4	End	N/A	N/A	N/A	N/A

💡 All steps completed, variable type checked by both functions.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
$var	undefined	123 (int)	123 (int)	123 (int)	123 (int)

Key Moments - 2 Insights

Why does gettype() return "integer" but get_debug_type() returns "int"?

gettype() returns the full type name as a string like "integer", while get_debug_type() returns a shorter alias like "int". See execution_table steps 2 and 3.

Can get_debug_type() be used in all PHP versions?

No, get_debug_type() was introduced in PHP 8.0. gettype() works in all versions. This is why get_debug_type() is called after gettype() in the execution.

Visual Quiz - 3 Questions

Look at the execution table, what is the output of gettype($var) at step 2?

A "string"

B "int"

C "integer"

D "number"

💡 Hint

Check the 'Output' column in execution_table row for step 2.

At which step does the variable $var get defined?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the 'Action' and 'Variable' columns in execution_table.

If $var was a string "hello", what would gettype($var) output?

A "int"

B "string"

C "integer"

D "bool"

💡 Hint

gettype() returns the type name as a string, see how it outputs "integer" for an int in execution_table step 2.

Concept Snapshot

PHP gettype() returns the type of a variable as a string like "integer".
PHP get_debug_type() (PHP 8.0+) returns a shorter type name like "int".
Use gettype() for compatibility with older PHP versions.
Both help check variable types during debugging or logic.
Example: gettype(123) -> "integer", get_debug_type(123) -> "int".

Full Transcript

This example shows how PHP checks variable types using gettype() and get_debug_type(). First, a variable $var is set to 123, an integer. Then gettype($var) is called, which returns the string "integer". Next, get_debug_type($var) is called, returning "int". The difference is that gettype() returns the full type name, while get_debug_type() returns a shorter alias. get_debug_type() requires PHP 8.0 or newer. This helps programmers understand what type a variable holds at runtime.