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Show HN: Practical programming language with expressive power, in 10K LOC C++11

2 points by rusini 7y ago

karmakaze 7y ago
> the syntax of MANOOL is actually so simple that it could be “described on a postcard”. This immediately makes me want to read said postcard. Is there something to this effect? [Couldn't find it.] I didn't see the advantage in using braces instead of Lisp-parens or functional languages that use neither. The first thought that came to mind was using the semi-colon insertion parsing like Go, but on source text that uses whitespace indentation like Python and insert all the braces needed by the parser.
- karmakaze 7y ago
  Also, all the Wikipedia links are annoying. Assume we know how to use the internet. I wanted every link to show me relevant content (e.g. benchmarks[0] :-) [0] https://en.wikipedia.org/wiki/Benchmark_(computing) https://en.wikipedia.org/wiki/Benchmark_(computing)
  - rusini 7y ago
    Sorry, I did not had time to add that content (I was in hurry to show my work and at least make an intro, after 4 years of silence and hard work :-) BUT thank you for the suggestion! I will include those benchmarks shortly. Refs to wikipedia help me to focus on using common terminology as much as possible (and I actually wrote the Intro also for some of my friends that do not understand what "programming" means if I do not speak of "computer programming" and add a link to wikipedia :-). BTW personally, I also find hyperrefs annoying aesthetically...
    - karmakaze 7y ago
      It would help a lot if the wikipedia links were visually identified by a little 'definition' graphic or something. Congrats, it looks very complete and is a great achievement.
- rusini 7y ago
  Thank your for commenting! > This immediately makes me want to read said postcard. Is there something to this effect? [Couldn't find it.] I actually did not do such exercise, sorry :-) BUT: 1) almost all syntactic features are demonstrated in the first two examples/lessons in the wiki (and could be compressed further); 2) the formal context-free grammar can be found in the large PDF (caution: crude, work in progress!): https://github.com/rusini/manool/releases/download/v0.2-beta/MANOOL.pdf https://github.com/rusini/manool/releases/download/v0.2-beta... It has only 25 rules. That's comparable with Smalltalk. Besides, Smalltalk was a source of inspiration for the syntax, since it is culturally a cousin of LISP, does not use S-expressions, but its syntax does allow for a kind of DSLs (think ... ifTrue: ...). MANOOL is similar in that respect, but its syntax is closer to S-expressions (allows you to express name bindings). >I didn't see the advantage... S-expressions have syntactic sugar to express lists: (A B C) -> (A . (B . (C . ()))) MANOOL has that and slightly more: infix/postfix operators (and one prefix), etc.: A[B; C] -> {A B C}, A + B -> {(+) A B}, {A: B C} -> {A {B C}}, A.B[C] -> {B A C}, etc... (it does not have dotted pair notation, but I hope the idea is clear). That syntactic sugar is abstract and independent of what actually A[B; C] and A + B mean. The intention, for example, is that the syntax (at the context-free grammar level - surface syntax) does not need to change no matter what features we need in the future. It is said that context-free grammars are not modular: as the language evolves it is easy to introduce ambiguities (think C++). MANOOL approach does not suffer from that; features (like keywords if, while...) can even be made available selectively in a limited scope, if needed. I call it "universal grammar". On the other hand, I strongly suspect that the resulting syntax is better than S-expressions "psychologically" (sorry LISP'ers :-). It is not a matter of our familiarity with infix notations (from mid school), but our brain has very limited "stack". Anyway, the point of MANOOL is not its syntax or homoiconicity; it was originally just a nice implementation strategy. The point lies deeper in some semantic features... BTW that's not the first time that someone comes and suggests something to replace S-expressions and... fails. BUT one successful example is Smalltalk (albeit the result is not quite "homoiconic"), so that inspired me too. As to why {} instead of ()... the main reason is that () had to be reserved for explicit grouping of subexpressions (just like in mid school or Smalltalk): (1 + 2) * 3. BTW that's why I had to use [] for "applications" and that might look ugly to people (but think about failed M-expressions). As to optional ";", that was precisely one of those "design compromises" I am talking about. Personally, I am not a fan of "semicolon omissions" :-)
- rusini 7y ago
  Well, what about this program?: -- factorial { {extern "manool.org.18/std/0.2/all"} in : let { Fact = { proc { N } as : unless N.IsI48[] & (N >= 1 - 1) signal {if (~)[N.IsI48[]] then TypeMismatch else InvariantViolation} else : var { Res = 1 } in : do Res after : while N <> 0 do Res = N * Res; N = N + ~1 } } in Out.WriteLine[/* Out; */ "Factorial of 10 is "; Fact[10]$] } It has absolutely all syntactic features and even makes sense!
  - karmakaze 7y ago
    I find the nesting of elements hard to follow and would prefer something like: -- factorial (extern "manool.org.18/std/0.2/all") in: let: Fact = proc { N } as: unless N.IsI48[] & (N >= 1 - 1) signal (if (~)[N.IsI48[]] then TypeMismatch else InvariantViolation) else: var { Res = 1 } in do Res after while N <> 0 do Res = N * Res; N = N + ~1 in: Out.WriteLine[/* Out; */ "Factorial of 10 is "; Fact[10]$]

2 points by rusini 7y ago

> the syntax of MANOOL is actually so simple that it could be “described on a postcard”. This immediately makes me want to read said postcard. Is there something to this effect? [Couldn't find it.] I didn't see the advantage in using braces instead of Lisp-parens or functional languages that use neither. The first thought that came to mind was using the semi-colon insertion parsing like Go, but on source text that uses whitespace indentation like Python and insert all the braces needed by the parser.

karmakaze 7y ago
Also, all the Wikipedia links are annoying. Assume we know how to use the internet. I wanted every link to show me relevant content (e.g. benchmarks[0] :-) [0] https://en.wikipedia.org/wiki/Benchmark_(computing) https://en.wikipedia.org/wiki/Benchmark_(computing)
- rusini 7y ago
  Sorry, I did not had time to add that content (I was in hurry to show my work and at least make an intro, after 4 years of silence and hard work :-) BUT thank you for the suggestion! I will include those benchmarks shortly. Refs to wikipedia help me to focus on using common terminology as much as possible (and I actually wrote the Intro also for some of my friends that do not understand what "programming" means if I do not speak of "computer programming" and add a link to wikipedia :-). BTW personally, I also find hyperrefs annoying aesthetically...
  - karmakaze 7y ago
    It would help a lot if the wikipedia links were visually identified by a little 'definition' graphic or something. Congrats, it looks very complete and is a great achievement.
rusini 7y ago
Thank your for commenting! > This immediately makes me want to read said postcard. Is there something to this effect? [Couldn't find it.] I actually did not do such exercise, sorry :-) BUT: 1) almost all syntactic features are demonstrated in the first two examples/lessons in the wiki (and could be compressed further); 2) the formal context-free grammar can be found in the large PDF (caution: crude, work in progress!): https://github.com/rusini/manool/releases/download/v0.2-beta/MANOOL.pdf https://github.com/rusini/manool/releases/download/v0.2-beta... It has only 25 rules. That's comparable with Smalltalk. Besides, Smalltalk was a source of inspiration for the syntax, since it is culturally a cousin of LISP, does not use S-expressions, but its syntax does allow for a kind of DSLs (think ... ifTrue: ...). MANOOL is similar in that respect, but its syntax is closer to S-expressions (allows you to express name bindings). >I didn't see the advantage... S-expressions have syntactic sugar to express lists: (A B C) -> (A . (B . (C . ()))) MANOOL has that and slightly more: infix/postfix operators (and one prefix), etc.: A[B; C] -> {A B C}, A + B -> {(+) A B}, {A: B C} -> {A {B C}}, A.B[C] -> {B A C}, etc... (it does not have dotted pair notation, but I hope the idea is clear). That syntactic sugar is abstract and independent of what actually A[B; C] and A + B mean. The intention, for example, is that the syntax (at the context-free grammar level - surface syntax) does not need to change no matter what features we need in the future. It is said that context-free grammars are not modular: as the language evolves it is easy to introduce ambiguities (think C++). MANOOL approach does not suffer from that; features (like keywords if, while...) can even be made available selectively in a limited scope, if needed. I call it "universal grammar". On the other hand, I strongly suspect that the resulting syntax is better than S-expressions "psychologically" (sorry LISP'ers :-). It is not a matter of our familiarity with infix notations (from mid school), but our brain has very limited "stack". Anyway, the point of MANOOL is not its syntax or homoiconicity; it was originally just a nice implementation strategy. The point lies deeper in some semantic features... BTW that's not the first time that someone comes and suggests something to replace S-expressions and... fails. BUT one successful example is Smalltalk (albeit the result is not quite "homoiconic"), so that inspired me too. As to why {} instead of ()... the main reason is that () had to be reserved for explicit grouping of subexpressions (just like in mid school or Smalltalk): (1 + 2) * 3. BTW that's why I had to use [] for "applications" and that might look ugly to people (but think about failed M-expressions). As to optional ";", that was precisely one of those "design compromises" I am talking about. Personally, I am not a fan of "semicolon omissions" :-)
rusini 7y ago
Well, what about this program?: -- factorial { {extern "manool.org.18/std/0.2/all"} in : let { Fact = { proc { N } as : unless N.IsI48[] & (N >= 1 - 1) signal {if (~)[N.IsI48[]] then TypeMismatch else InvariantViolation} else : var { Res = 1 } in : do Res after : while N <> 0 do Res = N * Res; N = N + ~1 } } in Out.WriteLine[/* Out; */ "Factorial of 10 is "; Fact[10]$] } It has absolutely all syntactic features and even makes sense!
- karmakaze 7y ago
  I find the nesting of elements hard to follow and would prefer something like: -- factorial (extern "manool.org.18/std/0.2/all") in: let: Fact = proc { N } as: unless N.IsI48[] & (N >= 1 - 1) signal (if (~)[N.IsI48[]] then TypeMismatch else InvariantViolation) else: var { Res = 1 } in do Res after while N <> 0 do Res = N * Res; N = N + ~1 in: Out.WriteLine[/* Out; */ "Factorial of 10 is "; Fact[10]$]