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What does a type being built-in do for you extra? In ES6 you can define a template string builder which you could name, for instance, ipv4, and then when you wa

What does a type being built-in do for you extra? In ES6 you can define a template string builder which you could name, for instance, ipv4, and then when you want an IPv4 address literal you say ipv4`192.168.0.1` and get your object. Are there other benefits besides a literal syntax? (Not to slag on Red. One advantage I can see is avoiding the call at runtime to the ipv4 function.)

greggirwin 10y ago
One of the key reasons for having a lot of literal forms is because REBOL was designed as a messaging language. You can think of it as a data format as much as anything. Template literals in ES6 help with DSL support, which is fundamental in Red's design. It doesn't mean you can just include anything in Red, but the wide array of native forms lets you build a lot of embedded DSLs without resorting to string parsing. Being able to parse at the block level (i.e. datatype level) is really nice. A couple other new features make dealing with non-loadable input easier too. You can use macros to pre-process data, trap errors that `load` triggers and still get back a block of values, or spec some simple rules in `system/lexer/pre-load`. That's another way we might deal with IPv6 values.
- pekr 10y ago
  Yes, a message format. What I would add is, that today ppl are using JSON, not realising, that it is de-facto a Rebol, or at least strongly inspired by Rebol. Well - who wants to use cryptic formats anyway, right? :-)
greggirwin 10y ago
I'll add to my reply, because this is a really good question. Red doesn't have all types in place yet (e.g. date! is coming, and maybe an @ref type, among others), but can still load the following: at 10:00 send gregg@host.dom a link to http://red-lang.org (216.239.32.21) delete %/c/temp/junk.dat assign #DECAFBAD-7337 to John make the main window 800x600 with a color of 255.0.0 answer: yes Here's a quick console session showing what types it found: >> blk: [ at 10:00 send gregg@host.dom a link to http://red-lang.org (216.239.32.21) [ delete %/c/temp/junk.dat [ assign #DECAFBAD-7337 to John [ make the main window 800x600 with a color of 255.0.0 [ answer: yes [ ] == [at 10:00:00 send gregg@host.dom a link to http://red-lang.org (216.239.32.21) delete %/c/temp/junk.dat >> unique collect [foreach val blk [keep type? val]] == [word! time! email! url! paren! file! issue! pair! tuple! set-word!] And you can parse at that level: >> parse blk [ [ some [ [ 'window set val pair! (print ["size:" val]) [ | 'assign set val issue! (print ["issue:" val]) [ | 'link 'to set val url! (print ["link:" val]) [ | skip [ ] [ ] link: http://red-lang.org issue: DECAFBAD-7337 size: 800x600 Of course, you could do something similar in ES6. If you use template literals, your data might look like this: at time`10:00` send email`gregg@host.dom` a link to url`http://red-lang.org` paren`(ipv4`216.239.32.21`)` delete file`%/c/temp/junk.dat` assign issue`#DECAFBAD-7337` to John make the main window pair`800x600` with a color of color`255.0.0` name`answer:` bool`yes` Sorry for getting carried away. :)
- abecedarius 10y ago
  That does look handy! I guess there must be a tradeoff in having your text default to meaning plain words if you mess up the syntax? Versus hopefully getting an error in the ES6 case.
  - greggirwin 10y ago
    You can always get errors of course. The new `load/trap` feature gives you more flexibility in that area, but there are limits as with anything. Pretty handy for CLIs, though, when you expect your audience to know what "syntax" even means. :)
- dmitriid 10y ago
  What are the chances of authors getting the types like email and uri incorrect? Oh, very high I would say
- vram22 10y ago
  No need to apologize, that was a good example :) I liked this big: >> unique collect [foreach val blk [keep type? val]] == [word! time! email! url! paren! file! issue! pair! tuple! set-word!] I think it could almost be read and understood by a person who does not know REBOL or Red.
  - greggirwin 10y ago
    Yup. We often write code like normal programmers, but sometimes we do build up vocabularies more, even when not using `parse` to write DSLs. "Red or REBOL" = Redbol (sounds like Red Bull) :) And where Perl has Mongers, Ruby has Rubyists, Python has Pythonistas, and Rebol has Rebolers, Red has Reducers.
    - vram22 10y ago
      Ha, Reducers is a good term, considering: the goals of Red (reducing complexity being one), the small size of Red (and REBOL) programs that get non-trivial things done, and finally the size of the software itself (the interpreter - and also compiler in the case of Red). Even the small EXE sizes, in fact (though I've only created EXEs for small programs so far, with it).

greggirwin 10y ago

One of the key reasons for having a lot of literal forms is because REBOL was designed as a messaging language. You can think of it as a data format as much as anything. Template literals in ES6 help with DSL support, which is fundamental in Red's design. It doesn't mean you can just include anything in Red, but the wide array of native forms lets you build a lot of embedded DSLs without resorting to string parsing. Being able to parse at the block level (i.e. datatype level) is really nice. A couple other new features make dealing with non-loadable input easier too. You can use macros to pre-process data, trap errors that `load` triggers and still get back a block of values, or spec some simple rules in `system/lexer/pre-load`. That's another way we might deal with IPv6 values.

pekr 10y ago
Yes, a message format. What I would add is, that today ppl are using JSON, not realising, that it is de-facto a Rebol, or at least strongly inspired by Rebol. Well - who wants to use cryptic formats anyway, right? :-)

greggirwin 10y ago

I'll add to my reply, because this is a really good question. Red doesn't have all types in place yet (e.g. date! is coming, and maybe an @ref type, among others), but can still load the following: at 10:00 send gregg@host.dom a link to http://red-lang.org (216.239.32.21) delete %/c/temp/junk.dat assign #DECAFBAD-7337 to John make the main window 800x600 with a color of 255.0.0 answer: yes Here's a quick console session showing what types it found: >> blk: [ at 10:00 send gregg@host.dom a link to http://red-lang.org (216.239.32.21) [ delete %/c/temp/junk.dat [ assign #DECAFBAD-7337 to John [ make the main window 800x600 with a color of 255.0.0 [ answer: yes [ ] == [at 10:00:00 send gregg@host.dom a link to http://red-lang.org (216.239.32.21) delete %/c/temp/junk.dat >> unique collect [foreach val blk [keep type? val]] == [word! time! email! url! paren! file! issue! pair! tuple! set-word!] And you can parse at that level: >> parse blk [ [ some [ [ 'window set val pair! (print ["size:" val]) [ | 'assign set val issue! (print ["issue:" val]) [ | 'link 'to set val url! (print ["link:" val]) [ | skip [ ] [ ] link: http://red-lang.org issue: DECAFBAD-7337 size: 800x600 Of course, you could do something similar in ES6. If you use template literals, your data might look like this: at time`10:00` send email`gregg@host.dom` a link to url`http://red-lang.org` paren`(ipv4`216.239.32.21`)` delete file`%/c/temp/junk.dat` assign issue`#DECAFBAD-7337` to John make the main window pair`800x600` with a color of color`255.0.0` name`answer:` bool`yes` Sorry for getting carried away. :)

abecedarius 10y ago
That does look handy! I guess there must be a tradeoff in having your text default to meaning plain words if you mess up the syntax? Versus hopefully getting an error in the ES6 case.
- greggirwin 10y ago
  You can always get errors of course. The new `load/trap` feature gives you more flexibility in that area, but there are limits as with anything. Pretty handy for CLIs, though, when you expect your audience to know what "syntax" even means. :)
dmitriid 10y ago
What are the chances of authors getting the types like email and uri incorrect? Oh, very high I would say
vram22 10y ago
No need to apologize, that was a good example :) I liked this big: >> unique collect [foreach val blk [keep type? val]] == [word! time! email! url! paren! file! issue! pair! tuple! set-word!] I think it could almost be read and understood by a person who does not know REBOL or Red.
- greggirwin 10y ago
  Yup. We often write code like normal programmers, but sometimes we do build up vocabularies more, even when not using `parse` to write DSLs. "Red or REBOL" = Redbol (sounds like Red Bull) :) And where Perl has Mongers, Ruby has Rubyists, Python has Pythonistas, and Rebol has Rebolers, Red has Reducers.
  - vram22 10y ago
    Ha, Reducers is a good term, considering: the goals of Red (reducing complexity being one), the small size of Red (and REBOL) programs that get non-trivial things done, and finally the size of the software itself (the interpreter - and also compiler in the case of Red). Even the small EXE sizes, in fact (though I've only created EXEs for small programs so far, with it).