include::../description.adoc[]

== Noncompliant Code Example

[source,php]
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"/[0-99]/" // Noncompliant, this won't actually match strings with two digits
"/[0-9.-_]/" // Noncompliant, .-_ is a range that already contains 0-9 (as well as various other characters such as capital letters)
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== Compliant Solution

[source,php]
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"/[0-9]{1,2}/"
"/[0-9.\\-_]/"
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