What is the purpose of do notation

Damm even I am having a similar kind of issue, I have searched all over the internet and even have posted on number of threads on different forum, no solution seems to work. I am really frustrated, can anyone of you here help me resolve this issue, I am very much tired now.

What is the purpose of do notation

> Now I see why it is so :). Because it's a hack that doesn't look good enough > to be included into the language. But that's a sad news. Type infer, at the > very least for anonymous functions, is very useful and important feature... 1. No, it's not a very "important feature", it's pretty muc

What is the purpose of do notation

Pass result as argument, then it wont use auto

What is the purpose of do notation

> Now I see why it is so :). Because it's a hack that doesn't look good enough > to be included into the language. But that's a sad news. Type infer, at the > very least for anonymous functions, is very useful and important feature... I dunno, I wouldn't call the `=>` itself a hack, it uses what

What is the purpose of do notation

> This is the same old problem — Nim doesn't have backward type inference. The > => macro does argument type “inference” in a hacky way by making the function > generic, but I'm not sure if that's appropriate for a language construct. Aha... it explains this mystery. I was always wondering why `

What is the purpose of do notation

test _12_

What is the purpose of do notation

I was not against nor in favor of it, it was just raw new-user feedback.

What is the purpose of do notation

It does not really make sense to put two-three line procedure (that might also be a closure btw, so it can't really be moved to toplevel) to the toplevel, and cramming all of this in the `=>` notation is not always possible as well.

What is the purpose of do notation

Regarding `quote do`, I see no reason why the `do` is necessary for this. Still waiting for someone to explain why it uses `do`. Why can't `quote` just work? Regarding @yglukhov's examples, personally I think the proc syntax is perfectly good, your style just needs a tweak :) foo(a

What is the purpose of do notation

> but I'm not sure if that's appropriate for a language construct. I think it's completely acceptable. Esp for alexeypetrushin.

What is the purpose of do notation

This is the same old problem — Nim doesn't have backward type inference. The `=>` macro does argument type “inference” in a hacky way by making the function generic, but I'm not sure if that's appropriate for a language construct.

What is the purpose of do notation

> 1 do is used frequently, see posts above of yours. > 2 do works as it is > documented, see point (1) > 3 Ruby had no significant influence on Nim's > design, sorry. 1. Ok, maybe, although I don't think `do` is used frequently, and I haven't seen such usage in other's people code. 2. I phr

What is the purpose of do notation

We have 873 `do`\- lambda occurrences in our private codebase :) . Although they can be replaced with anonymous procs, they slightly add to syntactical ergonomics and readability IMO. Compare this: foo(a, b) do(c, d: int) -> int: # Some body here return c + d

What is the purpose of do notation

Well... > Situation is similar here. Nobody uses it because do implemented poorly. I > from Ruby experience, like do, and tried to use it in Nim. But it doesn't > work. 1. `do` is used frequently, see posts above of yours. 2. `do` works as it is documented, see point (1) 3. Ruby had no si

What is the purpose of do notation

> I never really used do outside of quote do, and never seen used too much in > the wild neither, and people want to have else in more places, like > for...else, try...else, etc in Python. Reminds me about issue Youtube had couple of years ago. They improved Front-End performance, made it light

What is the purpose of do notation

> I think that theres alternatives already in std/genasts, fusion/astdsl, etc. @juancarlospaco \- sure, but I just did a search and in the whole nimbleverse not even one package imports `genasts`. The compiler/stdlib itself only tests it, instead using `quote do:`. The only thing I found anywher

What is the purpose of do notation

Good question, one I've had for a while myself.

What is the purpose of do notation

I think that theres alternatives already in std/genasts, fusion/astdsl, etc.

What is the purpose of do notation

> I think a real benefit is simplifying Nim. Costs vs benefits. The costs are high and `do` is only syntax so you don't simplify the language a whole lot. I'd rather throw away Nim's effect system. ;-) > but if someone is passionate enough to create a PR which deprecates it and > introduces th

What is the purpose of do notation

Is there any difference between `quote do:` and just `quote:`?

What is the purpose of do notation

@juancarlospaco \- ok, but there are literally 1000s of calls to quote do: in the nimbleverse alone. So, we probably can never get rid of it, but that doesn't mean we cannot make it better. @dom96 \- The easy path here might be to just allow `do` to accept **_optional parameter names_**. We cou

What is the purpose of do notation

I never really used `do` outside of `quote do`, and never seen used too much in the wild neither, and people want to have `else` in more places, like `for...else`, `try...else`, etc in Python.

What is the purpose of do notation

FWIW, user-specifiable keywords at definition/part of the call signature might be both backward compatible and nicely more general. E.g. `template[phase2, phase3] foo(phase1, phase2, phase3)` where the desired `else` might be `template[else] withValue(...)`. That seems like it'd be trickier, tho

What is the purpose of do notation

There is also probably a whole lot of `quote do:` code out there. While it may not be the most robust kind of macro metaprogramming, that general area is one of Nim's very distinctive features. `algorithm.sort` docs still direct users to use `do` instead of a `(proc(): int =)` lambda syntax. So

What is the purpose of do notation

I think a real benefit is simplifying Nim. It's definitely not a priority and there is plenty of other more important things to do, but if someone is passionate enough to create a PR which deprecates it and introduces the syntax above would you complain?

What is the purpose of do notation

No... I don't like `do` either but removing/changing/deprecating it at this point only has downsides. Maybe it's used in some code you like to use as a dependency, what then? Patch the dependency? And what if its author happens to like it? For everything we do we should do some basic "costs vs b

What is the purpose of do notation

The "do notation" is an overloaded feature of the language because it offers two things: * A different way to pass anonymous procs/closures to a procedure * A way to pass two code blocks to a template. Personally I've been arguing for the removal of the first use case for years now. For t

What is the purpose of do notation

It allows for code like: table.withValue("key", value): echo "value is ", value do: echo "key is not in table" Run

What is the purpose of do notation

Can someone please explain me purpose of do notation? What are its benefits in comparison to anonymous procs?