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# is_scalar

(PHP 4 >= 4.0.5)

is_scalar -- Finds whether a variable is a scalar

## Description

``bool is_scalar` (mixed var)`

is_scalar() returns `TRUE` if the variable given by the `var` parameter is a scalar, otherwise it returns `FALSE`.

Scalar variables are those containing an integer, float, string or boolean. For example:

    <!-- TODO: better example, this one can be quite misleading for unexperienced
               programmers -->
    function show_var($var) {
        if (is_scalar($var))
            echo $var;
        else
            var_dump($var);
    }

    $pi = 3.1416;
    $proteins = array("hemoglobin", "cytochrome c oxidase", "ferredoxin");

    show_var($pi);
    // prints: 3.1416

    show_var($proteins)
    // prints:
    // array(3) {
    //   [0]=>
    //   string(10) "hemoglobin"
    //   [1]=>
    //   string(20) "cytochrome c oxidase"
    //   [2]=>
    //   string(10) "ferredoxin"
    // }

> Note: is_scalar() does not consider resource type values to be scalar values. This behavior is intentional: Resources are abstract datatypes which are currently based on integers. This implementation detail should not be relied upon, as it may change.

> Note: Since 4.0.5

See also is_bool(), is_numeric(), is_float(), is_int(), is_real(), is_string(), is_object(), is_array(), and is_integer().

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