Interesting! I submitted a Phep a while back to implement a compile-time literal syntax ##() as seen in Dolphin Smalltalk, with literal collections like this as a major (though not exclusive) use-case. At the time I couldn't think of a way to do better for arbitrary collections, but this is a very natural extension of the brace-array syntax—clever use of the block-argument-esque leading colon. I still like some things about the flexibility of the compile-time literal approach, but this certainly has it beat for terseness in the common case! One question about the implementation—does it reduce straightforwardly to instantiation and repeated sends of `add:`, or a single `withAll:` or similar, or does it depend on knowledge of the underlying collection implementation? Put another way, would it work with a custom collection class? What about a class that isn't a descendant of Collection at all, but understands the right protocol? On Mon, Sep 18, 2023 at 3:16 PM Noury Bouraqadi <bouraqadi@gmail.com> wrote:

Cool!

Noury On Sep 18 2023, at 5:20 pm, stephane ducasse <stephane.ducasse@inria.fr> wrote:

In a Phep005 soon available

testLiteralSet

| compiler | compiler := OpalCompiler new. compiler compilationContext parserClass: RBParserLiteralCollection. self assert: (compiler evaluate: '{ :Set 1 . 2 . 1}' )

equals: #(1 2) asSet.

testOrderedCollection

| compiler | compiler := OpalCompiler new. compiler compilationContext parserClass: RBParserLiteralCollection. self assert: (compiler evaluate: '{ :OrderedCollection 1 . 2 . 1 . 3}' )

equals: #(1 2 1 3) asOrderedCollection.

testDictionary

| compiler dict | compiler := OpalCompiler new. compiler compilationContext parserClass: RBParserLiteralCollection. dict := (compiler evaluate: '{ :Dictionary #a -> 33 . #b -> 44}' ). self assert: (dict at: #a) equals: 33