Jira (PUP-7277) Add Init[T] type to type system

[Henrik Lindberg (JIRA)]

Title: Message Title

Henrik Lindberg commented on PUP-7277   Re: Add Init[T] type to type system Well, the type itself is only a matcher for an instance that when combined with the argument given to the type is a valid signature for the types new function. As an example this will notice true for the two matches against Init: type Artist = Object[{ attributes => { name => String, genre => String}}] $mega_death = Artist({name => 'Megadeath', genre => 'Metal'}) notice( { name => 'Bananarama', genre => 'Pop'} =~ Init[Artist] ) notice( $mega_death =~ Init[Artist] ) The arguments that can be added to Init are literal values that would typically be some kind of formats/flags - as an example the Timestamp type supports an array of time formats, and a timezone to Timestamp.new. The intent is to use the Init type in signatures to signal that a type cast/conversion is wanted. For example: class myclass(Init[Timestamp] $when) { # $when will be an instance of Timestamp } This would accept a String from APL if that string is a valid initializer for a Timestamp. This ticket is only about the Init type itself, making it into a type transformation/casting operation is a separate ticket. So - there are two main use cases: APL - since it is difficult to represent some data types in JSON/YAML In literal nested Pcore models to save typing (that is; instead of having to write this to create an array of two artists: [ Artist({name => 'Megadeath', genre => 'Metal'}), Artist({ name => 'Bananarama', genre => 'Pop'}) ] You can write: [ {name => 'Megadeath', genre => 'Metal'}, { name => 'Bananarama', genre => 'Pop'} ] when that is assigned to an attribute of type Array[Artist]. This is of particular value when the names of the types are long - in nested name spaces (as is typical with types used with Netconf/Yang). Add Comment   This message was sent by Atlassian JIRA (v6.4.14#64029-sha1:ae256fe) -- You received this message because you are subscribed to the Google Groups "Puppet Bugs" group. To unsubscribe from this group and stop receiving emails from it, send an email to puppet-bugs+unsubscr...@googlegroups.com. To post to this group, send email to puppet-bugs@googlegroups.com. Visit this group at https://groups.google.com/group/puppet-bugs. For more options, visit https://groups.google.com/d/optout.