Data::Sah::DefaultValueCommon - Common stuffs for Data::Sah::DefaultValue and Data::Sah::DefaultValueJS


This document describes version 0.005 of Data::Sah::DefaultValueCommon (from Perl distribution Data-Sah-DefaultValue), released on 2024-01-17.




 get_default_value_rules(%args) -> [$status_code, $reason, $payload, \%result_meta]

Get default-value rules.

This routine determines default-value rule modules to use (based on the default_value_rules specified), loads them, filters out modules with old/incompatible metadata version, and return the list of rules.

This common routine is used by Data::Sah compilers, as well as Data::Sah::DefaultValue and Data::Sah::DefaultValueJS.

This function is not exported.

Arguments ('*' denotes required arguments):

  • compiler* => str

    (No description)

  • default_value_rules => array[str]

    A specification of default-value rules to use (or avoid).

    This setting is used to specify which default-value rules to use (or avoid) in a flexible way. Each element is a string, in the form of either NAME to mean specifically include a rule, or !NAME to exclude a rule.

    To use the default-value rules R1 and R2:

     ['R1', 'R2']
  • extra_args => hash

    Extra arguments to pass to value() subroutine.

    This is used, for example, by Data::Sah when generating validation code from Sah schema. Sometimes the default value rule needs to know additional information like what a date type should be coerced to (DateTime object, or epoch) so it can generate the appropriate default value.

Returns an enveloped result (an array).

First element ($status_code) is an integer containing HTTP-like status code (200 means OK, 4xx caller error, 5xx function error). Second element ($reason) is a string containing error message, or something like "OK" if status is 200. Third element ($payload) is the actual result, but usually not present when enveloped result is an error response ($status_code is not 2xx). Fourth element (%result_meta) is called result metadata and is optional, a hash that contains extra information, much like how HTTP response headers provide additional metadata.

Return value: (any)


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