On Mon, Mar 6, 2017 at 5:54 PM, Sven Van Caekenberghe <s...@stfx.eu> wrote:
> Here is a concrete proposal: > > https://pharo.fogbugz.com/f/cases/19802/Make-sure-Symbol- > concatenation-results-in-a-Symbol-not-a-String > > This gives the following assertions: > > "Concatenating 2 symbols results in abother symbol" > self assert: (#foo , #bar) == #foobar. > > "Concatenating the empty symbol does not change a symbol" > self assert: (#foo, emptySymbol) == #foo. > self assert: (emptySymbol, #foo) == #foo. > > "Strings and symbols can still be mixed, the receiver determines > the result type" > "Symbol receiver gives symbol result" > self assert: (#foo , 'bar') == #foobar. > "String receiver gives string result" > self deny: ('foo' , #bar) == #foobar. > self assert: ('foo' , #bar) equals: #foobar. > self assert: ('foo' , #bar) equals: 'foobar'. > Those last two seem contradictory. cheers -ben > > > On 5 Mar 2017, at 19:53, Martin McClure <mar...@hand2mouse.com> wrote: > > > > On 03/05/2017 03:01 AM, Sven Van Caekenberghe wrote: > >> I also think that allowing concatenation on Symbols does not violate > their immutability contract. > >> > >> As a thought experiment, what could be the problem with adding > >> > >> Symbol >> , arg > >> ^ (self , arg) asSymbol > >> > >> ? > >> > > > > Aside from the infinite recursion (I suspect you meant super rather than > self) :-) , I wouldn't have any problem with that. > > > >> > >> (I have found the original issue raised annoying as well) > >> > >> > >>> On 5 Mar 2017, at 11:35, Peter Uhnak <i.uh...@gmail.com> > >>> wrote: > >>> > >>> I don't need (or want) to mutate the receiver. Actually I thought that > String is also immutable. > >>> $, could just return a new symbol instance instead. Concating symbols > is quite practical for metaprogramming, as most things are named with > symbols and compare by identity... > >>> > > Somewhat unfortunately, imho, Smalltalk Strings are mutable. I've not > seen this feature used often, except by internal operations that could just > as well be using a CharacterBuffer or whatever would replace String as the > mutable thing if you made String immutable. > > > > Regards, > > > > -Martin > > >
