Pattern Matching Conversion (P)
The P conversion code attempts to match the supplied data against one or more pattern templates
The full format of this conversion code is
The P conversion code tests whether the input data matches template. If a match is found, the original data is returned. If no match is found, a null string is returned.
If more than one template is provided, the input value is tested against each in turn.
A null input value always returns a null result.