Useful¶

new

Standard constructor. Returns a blessed hash; any arguments are placed in the hash. This is useful for storing information between methods.

generic_parser

This is a method provided solely for the benefit of "Parser" implementations. It semi-neatly abstracts a lot of the work involved.

Basically, it takes parameters matching the assorted callbacks from the parser declarations and makes a coderef out of it all.

Currently recognized callbacks are:

• on_match
• on_fail
• preprocess
• postprocess

Methods for subclassing¶

These are methods you should define when writing your own subclass.

Note: these methods do not exist in this class. There is no point trying to call "$self->SUPER::do_match( ... )".

do_match

"do_match" is the first phase. Arguments are the date and @args. "self", "label", "args". Return value must be defined if you match successfully.

post_match

"post_match" is called after the appropriate callback out of "on_match"/"on_fail" is done. It's passed the date, the return value from "do_match" and the parsing hash.

Its return value is used as the "post" argument to the "postprocess" callback, and as the second argument to "make".

make

"make" takes the original input, the return value from "post_match" and the parsing hash and should return a "DateTime" object or undefined.

Delegations¶

For use of "Parser", this module also delegates "valid_params" and "params". This is just convenience to save typing the following:

    DateTime::Format::Builder::Parser->valid_params(...)

Instead we get to type:

    $self->valid_params(...);
    __PACKAGE__->valid_params(...);