4 ms·

I think possibly the greatest advantage Elixir has is offering the power of the Erlang/OTP system without weird quirks like Erlang’s string handling. I never ha

by jolux 4y ago

I think possibly the greatest advantage Elixir has is offering the power of the Erlang/OTP system without weird quirks like Erlang’s string handling. I never have to think about it in Elixir, binary UTF-8 strings are the default and there’s plenty of functions in the standard library for dealing with grapheme clusters and the like.

derefr 4y ago
Always wondered if Elixir loses anything by doing binary strings by default. Is there any problem-domain where it benefits you to have charlists over binary strings? (Lexing, maybe? I know leex expects its input to be a charlist, but I'm not sure whether that's just legacy of being developed before Erlang R5 when binaries were introduced.)
- toast0 4y ago
  I've done a lot of Erlang, but no Elixir; as long as you can still access charlists, I don't see what you might lose by having a much better default. Changing "foo" to mean something other than a list of codepoints in Erlang would cause a lot of trouble, but Elixir started when assuming utf8 binaries was clearly the right answer. Having a list of codepoints is kind of useful, but unicode gets pretty complex, some things are multiple codepoints but essentially indivisible (unicode flags, for example don't make much sense with only one code point), so codepoints aren't the useful unit that byte/characters are in 8-bit encodings.
  - derefr 4y ago
    > unicode flags, for example don't make much sense with only one code point Complete tangent, but: To me, the Unicode flag codepoints aren't really "combining codepoints with weird behavior" in the sense that e.g. a zero-width joiner is a combining codepoint with weird behavior; so much as they're a special alphabet that colors the text written in it as an ISO country code; where valid country-codes spelled out in that alphabet just happen to be ligature-rendered in a special way by font authors. It makes just as much sense to have an isolated Regional Indicator Symbol Letter C (U+1F1E8) in text as it does to have an isolated regular C in text. (HN strips out the former, but it does have a visual representation!) In both cases, they're one letter of a "word", and don't make sense to use, but do make sense to mention. You can talk about "countries whose ISO country codes start with U+1F1E8" just like you can talk about "countries whose names start with C." This is unlike e.g. the individual surrogate-pair codepoints in UTF-16, which don't make sense to use nor mention on their own. And it can also make sense to use the Regional Indicator Symbol Letters to spell out country-codes that don't exist, without the expectation that they'll be rendered as a flag at present; simply because you're adding a layer of semantic meaning to your text for machines (and potentially getting a future flag-symbol for humans as a bonus.) The meaning — "this text is colored to be an ISO country-code" — is still there, whether the text renders a flag or not. It's a forward-compatible encoding, in a way that "individual flag emojis for each country" wouldn't be. Mind you, I'm on the fence about whether I like the Unicode Committee's choice to implement these codepoints as a special alphabet. On the one hand, I appreciate that these characters need to be their own set of semantically-distinct codepoints in some sense, so that there's no semantic ambiguity of these being interpreted by machine-parsers as "letters in a word", like there would be if these were letters spelled out in the Wingdings font. But on the other hand, would it have really hurt the design of Unicode so much to just come up with a semantic-meaning equivalent to the Variation Selectors, so that we could just use regular letters A+Z, plus a prefix codepoint on each that means "interpreted as an ISO country-code"? Semiotics Selectors, per se?
  - throwawaymaths 4y ago
    The charlist wonkiness does bleed into elixir. Just about every other week or so there is someone confused on elixir forums: Here's one from 2 days ago: https://elixirforum.com/t/unexpected-output-from-enum-module-function/48418 https://elixirforum.com/t/unexpected-output-from-enum-module... I had a junior that came from python that did not want to work in elixir because he refused to write unit tests and the fact that double quotes were different from single quotes (and double quotes were default) he couldn't deal with -- joke was on him because python3 made strings a whole lot more complicated!
- arthurcolle 4y ago
  I relly don't think so. Charlists are like your appendix, maybe served some vestigial purpose but probably not too serious
throwawaymaths 4y ago
Yeah the fewer number of quirks is great but, first class tooling like ExUnit and Mix, and otp extensions like Task, DynamicSupervisor, and Registry are pretty hot, if you ask me, not to mention a package registry so good that Erlang is being encouraged to migrate to it...
- jolux 4y ago
  Very true. There's a lot to love about it!

by jolux 4y ago

derefr 4y ago

Always wondered if Elixir loses anything by doing binary strings by default. Is there any problem-domain where it benefits you to have charlists over binary strings? (Lexing, maybe? I know leex expects its input to be a charlist, but I'm not sure whether that's just legacy of being developed before Erlang R5 when binaries were introduced.)

toast0 4y ago
I've done a lot of Erlang, but no Elixir; as long as you can still access charlists, I don't see what you might lose by having a much better default. Changing "foo" to mean something other than a list of codepoints in Erlang would cause a lot of trouble, but Elixir started when assuming utf8 binaries was clearly the right answer. Having a list of codepoints is kind of useful, but unicode gets pretty complex, some things are multiple codepoints but essentially indivisible (unicode flags, for example don't make much sense with only one code point), so codepoints aren't the useful unit that byte/characters are in 8-bit encodings.
- derefr 4y ago
  > unicode flags, for example don't make much sense with only one code point Complete tangent, but: To me, the Unicode flag codepoints aren't really "combining codepoints with weird behavior" in the sense that e.g. a zero-width joiner is a combining codepoint with weird behavior; so much as they're a special alphabet that colors the text written in it as an ISO country code; where valid country-codes spelled out in that alphabet just happen to be ligature-rendered in a special way by font authors. It makes just as much sense to have an isolated Regional Indicator Symbol Letter C (U+1F1E8) in text as it does to have an isolated regular C in text. (HN strips out the former, but it does have a visual representation!) In both cases, they're one letter of a "word", and don't make sense to use, but do make sense to mention. You can talk about "countries whose ISO country codes start with U+1F1E8" just like you can talk about "countries whose names start with C." This is unlike e.g. the individual surrogate-pair codepoints in UTF-16, which don't make sense to use nor mention on their own. And it can also make sense to use the Regional Indicator Symbol Letters to spell out country-codes that don't exist, without the expectation that they'll be rendered as a flag at present; simply because you're adding a layer of semantic meaning to your text for machines (and potentially getting a future flag-symbol for humans as a bonus.) The meaning — "this text is colored to be an ISO country-code" — is still there, whether the text renders a flag or not. It's a forward-compatible encoding, in a way that "individual flag emojis for each country" wouldn't be. Mind you, I'm on the fence about whether I like the Unicode Committee's choice to implement these codepoints as a special alphabet. On the one hand, I appreciate that these characters need to be their own set of semantically-distinct codepoints in some sense, so that there's no semantic ambiguity of these being interpreted by machine-parsers as "letters in a word", like there would be if these were letters spelled out in the Wingdings font. But on the other hand, would it have really hurt the design of Unicode so much to just come up with a semantic-meaning equivalent to the Variation Selectors, so that we could just use regular letters A+Z, plus a prefix codepoint on each that means "interpreted as an ISO country-code"? Semiotics Selectors, per se?
- throwawaymaths 4y ago
  The charlist wonkiness does bleed into elixir. Just about every other week or so there is someone confused on elixir forums: Here's one from 2 days ago: https://elixirforum.com/t/unexpected-output-from-enum-module-function/48418 https://elixirforum.com/t/unexpected-output-from-enum-module... I had a junior that came from python that did not want to work in elixir because he refused to write unit tests and the fact that double quotes were different from single quotes (and double quotes were default) he couldn't deal with -- joke was on him because python3 made strings a whole lot more complicated!
arthurcolle 4y ago
I relly don't think so. Charlists are like your appendix, maybe served some vestigial purpose but probably not too serious

throwawaymaths 4y ago

Yeah the fewer number of quirks is great but, first class tooling like ExUnit and Mix, and otp extensions like Task, DynamicSupervisor, and Registry are pretty hot, if you ask me, not to mention a package registry so good that Erlang is being encouraged to migrate to it...

jolux 4y ago
Very true. There's a lot to love about it!