Hi Andy, Thanks for this, I hadn't realized there was a ticket and prior discussion. I've voted on the ticket and will add a mention of '#' and this thread to the ticket.
All best, steven On Tuesday, November 8, 2016 at 11:31:03 AM UTC-5, Andy Fingerhut wrote: > > Steven: > > Regarding Alex Miller's "Voting" message of today, you could consider > voting on this related ticket if you are so inclined: > http://dev.clojure.org/jira/browse/CLJ-1527 > > I just realized that having a warning in a lint tool like Eastwood for > using characters other than those explicitly endorsed in the documentation > might be useful. I also suspect a lot of people would want it off by > default, given that it might be fairly noisy for some projects. > > Andy > > On Tue, Nov 8, 2016 at 8:17 AM, Steven Yi <stev...@gmail.com <javascript:> > > wrote: > >> Hi Alex, >> >> Thanks for the reply, that was how I understood the intention of that >> text as well. It is ambiguous though, considering the discussion of >> auto-gensyms later in the page mentions: >> >> "If a symbol is non-namespace-qualified and ends with '#', it is >> resolved to a generated symbol with the same name to which '_' and a unique >> id have been appended. e.g. x# will resolve to x_123. All references to >> that symbol within a syntax-quoted expression resolve to the same generated >> symbol." >> >> Which is to say, the text describes symbol names and using '#'. >> >> Anyways, I get that '#' usage remains open for interpretation and later >> design decisions. I thought maybe because it was already used in >> auto-gensyms and because of how read() and syntaxQuote() relate in >> LispReader, it might mean that '#' became a definitive part of permitted >> symbol name characters. I think a second look at that made me realize it >> could still be reinterpreted. >> >> So, although I like the use of '#' for my use case, it's easy enough to >> revise my design to use a different character here. >> >> That said, wouldn't it better then for the compiler be made more >> restrictive now (i.e., only permit symbol names with '#' within syntax >> quote)? For example, the following compiles and runs fine in the REPL: >> >> (let [a# 4 b#a 3] (println a# b#3)) >> >> Because you're telling me I can not depend on '#' for symbols, I will >> have to make this change in some released code, where I had been using '#' >> in keywords, and that's a breaking change for my API. It would have been >> much nicer for me if such reserved things are treated as errors, so that I >> don't write valid code now that is at risk of breaking later. >> >> There are also other characters, such as '$', '%', '=', '&', '|', '>', >> '<', that also work now but are not listed in the website text regarding >> symbol names. Some, like '=', '>', and '<' are in common use as part of >> symbol names. ('$' seems often used with as->). As a user, I see one >> description in text, but in real world code I see other things in use, and >> that makes it confusing. It would be useful (to me at least) to have this >> be a little clearer what is reserved and what is not. >> >> Thanks! >> steven >> >> >> >> On Monday, November 7, 2016 at 8:38:28 PM UTC-5, Alex Miller wrote: >>> >>> >>> >>> On Monday, November 7, 2016 at 6:33:49 PM UTC-6, Steven Yi wrote: >>>> >>>> Hi All, >>>> >>>> I wanted to understand whether '#' may be treated as a valid character >>>> for symbols. The Clojure site [1] has: >>>> >>>> "Symbols begin with a non-numeric character and can contain >>>> alphanumeric characters and *, +, !, -, _, ', and ? (other characters >>>> may be allowed eventually)." >>>> >>> >>> The general advice here is that the characters listed here are >>> guaranteed to be valid now and in the future. Characters not listed here >>> may be accepted now or used within Clojure, but are not guaranteed to work >>> in the future. >>> >>> >>>> I realized I was using # today in a symbol without thinking much of >>>> it. However, the syntax highlighting in Vim marked it oddly when it >>>> was at the end of the symbol name versus in the middle of the name. >>>> (The use case is denoting musical notes using lists of symbols, such >>>> as '(c c# d eb) ). >>>> >>> >>> Same as above - this works now, but is not guaranteed to always be valid. >>> >>> auto-gensyms also employ # as part of symbol names, but I do not know >>>> if that should be considered a kind of special case. >>>> >>> >>> Same as above - Clojure may use these symbols to mean special things >>> (like auto gensyms in syntax quote), but that right is reserved for Clojure. >>> >>> >>>> Any clarifications appreciated! >>>> steven >>>> >>>> [1] - http://clojure.org/reference/reader >>>> >>> -- >> You received this message because you are subscribed to the Google >> Groups "Clojure" group. >> To post to this group, send email to clo...@googlegroups.com >> <javascript:> >> Note that posts from new members are moderated - please be patient with >> your first post. >> To unsubscribe from this group, send email to >> clojure+u...@googlegroups.com <javascript:> >> For more options, visit this group at >> http://groups.google.com/group/clojure?hl=en >> --- >> You received this message because you are subscribed to the Google Groups >> "Clojure" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to clojure+u...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
