Thanks Ben â itâs all clear now. Thanks also to Esteban, who spared my blushes by answering direct! Peter Kenny From: Pharo-users <pharo-users-bounces@lists.pharo.org> On Behalf Of Ben Coman Sent: 10 September 2018 19:56 To: Any question about pharo is welcome <pharo-users@lists.pharo.org> Subject: Re: [Pharo-users] Query on Pharo syntax On Tue, 11 Sep 2018 at 02:44, PBKResearch <peter@pbkresearch.co.uk <mailto:peter@pbkresearch.co.uk> > wrote: Hi All This is an idiot question, I should know the answer, but I have looked around and canât find relevant documentation. Iâm not asking for a full answer, just a pointer as to where to start looking. I have seen from examples in this forum that an expression like the following: paras collect: [para| para prettyPrinted] can be written more concisely as: paras collect: #prettyPrinted which obviously works when I try it. It doesnât seem to fit in with the definition of #collect:, which requires a block as argument. Where can I find the relevant definition, either in method comments or in some general manual? Can the notation be extended, Its not special notation. Just a normal object (a Symbol) passed via a normal message. for example to #select: - obviously with an argument which returns a Boolean? Can it be used with a method which requires an argument, e.g. as myArray collect: (#myMethod: arg)? Are there any other extensions? Any help gratefully received. Peter Kenny Full answer ;) Its a combination of the following two methods... Collection >> collect: aBlock | newCollection | newCollection := self species new. self do: [:each | newCollection add: (aBlock value: each)]. ^ newCollection Symbol value: anObject ^anObject perform: self. When /aBlock/ is a symbol, that symbol is performed on /each/ element. And looking at #select: , yes it works the same... Collection >> select: aBlock | newCollection | newCollection := self copyEmpty. self do: [ :each | (aBlock value: each) ifTrue: [ newCollection add: each ]]. ^newCollection cheers -ben