Testing castability of text to numeric

Hi All,

I am trying to create a function that will test if a given text value
may safely be cast to numeric, returning the numeric cast or null if
impossible.

Is there a way to "catch" the "ERROR: Bad numeric input format" error?

I ask that rather than about what the numeric format is for regex-style
testing because if this works I may want to use a similar method to
check if a given text value casts safely to other types, like date.

Best,

Randall