try to send the #on:do: message to a block. try this
^ [ (Date readFrom: self pattern: ‘dd/mm/yyyy’).
true ] on: DateError do: [ false].
On Tue, Mar 1, 2022 at 11:52 AM Robert Briggs via Pharo-users <
pharo-users@lists.pharo.org> wrote:
> I may be being stupid but the current Date Class does not appear to
> protect itself against a ByteString that is not in valid date format, e.g.
> by raising an Error.
>
>
>
> e.g. the code ‘ABC’ asDate opens the Debugger on #isLetter was sent to
> nil because it appears to expect more letters after $C but the peek
> returns nil instead.
>
> This seems to me to require a more defensive programming approach.
>
>
>
> I would like to validate a user input as a valid date in a number of
> different formats before converting it to a Date and storing it in my model.
>
>
>
> I’ve tried using the Date parser, e.g.
>
>
>
> Date readFrom: '04/02/2013' readStream pattern: 'dd/mm/yyyy'.
>
>
>
>
>
> This is fine for simply parsing a valid string but rates a DateError if it
> doesn’t match the . So entering ‘04/13/2013’ cleverly raises ‘DateError:
> There is no 13th month’.
>
>
>
> My thought was I could use this to return a simple true/false result in a
> ByteString extension in my application for example as follows:
>
>
>
> ByteString >> isValdiDate
>
>
>
> (Date readFrom: self pattern: ‘dd/mm/yyyy’) on: DateError do: [^ false].
>
> ^ true
>
>
>
> However this doesn’t intercept the DateError which is simply reported in
> the Debugger as before. This may be my lack of uncderstaning of the
> Exception handling in Pharo.
>
>
>
> Any and all thoughts welcome.
>
>
>
> R
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--
Bernardo E.C.
Sent from a cheap desktop computer in South America.
