variant_sub

(PHP 5, PHP 7)

variant_sub — Subtracts the value of the right variant from the left variant value

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variant_sub ( mixed $left , mixed $right ) : mixed

Subtracts right from left.

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left

The left operand.

right

The right operand.

Note:

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Variant Subtraction Rules
If Then
Both expressions are of the string type Subtraction
One expression is a string type and the other a character Subtraction
One expression is numeric and the other is a string Subtraction.
Both expressions are numeric Subtraction
Either expression is NULL NULL is returned
Both expressions are empty Empty string is returned

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  • variant_add() - "Adds" two variant values together and returns the result