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@didactic-drunk: should we add Process.fork to crystal-posix? @kevinsjoberg was asking about lack of
Process.fork. https://gist.github.com/postmodern/a98e68dff96163b5f234cd9de1c5c75d
2 replies
I'm trying to solve a visibility issue.
I have private class method
I have private class method
self.foo at the module level in one file, and in another file I have a struct defined in the same module. I would like some of the instance methods of the struct to be able to use the private foo method at the module level, but I cannot fully qualify it, and it is not part of the struct so I'm not sure if this is possible. I'm trying to write a file of private helper methods that are used in several other files/structs
Cancel that. I seemed to have figured out the right incantation to extend the module with private methods according to
crystal doc.
@didactic-drunk @kevinsjoberg hmm nevermind, looks like
Process.fork does exist but is nodoc'ed / part of the private API. https://github.com/crystal-lang/crystal/blob/1.0.0/src/process.cr#L62-L98
@Blacksmoke16: Maybe, though I'm not sure what that means for module methods...the docs talk about instances. I found a way with private though.
Mine probably doesn't do exactly what I expect.
Also, stupid question: I've never seen the double colon syntax for module name as in your example...where is this documented?
Is there a convention when naming methods that side-effect their instance? Some languages use a
! suffix.
But I see more of like .foo and.foo? Versus .foo! And.foo?
I think I decided on classes over structs. pass-by-value is sort of convoluting my API already.
re: yesterday's discussion
then can fix bottlenecks as needed, OR if the obj is for immutable and small
Yeah I chose structs first because this is ultimately going to be for high performance math routines used in math visualization animations
But that was a mistake...for now
that would prob be noticable diff
The math routines will typically have 2 different methods for each...one that allocates, and one that mutates...so, using classes should be fine, and I can always mutate a pre-allocated object before the loop
I mean I can always mutate inside the loop, a pre-existing object
My Lisp code I'd like to replace is over-optimized. I create temporary objects at init time and never allocate at runtime...heh
One thing that I still haven't gotten used to is blocks. It's very strange how methods are not first-class functions, coming from Lisp and a bit of Rust.
top-level variables being inaccessible in methods, intentionally restricting closures in favor of a separate construct (blocks).
I'm just not sure why that is the case compared to first-class functions. Maybe I don't fully understand blocks
Yeah, and I don't know how that differs from a lambda/anonymous function in other languages.
A method with a block is similar to a method that accepts an anonymous callback function
Yeah...it's just confusing me because lambda calculus is so simple and doesn't require any of that to do the same things.
module Origin
private DEFAULT_TOLERANCE = 1e-7
def self.=~(x : Float64, y : Float64, rel_tol : Float64 = DEFAULT_TOLERANCE, abs_tol : Float64 = rel_tol)
(x - y).abs <= Math.max(abs_tol, rel_tol * Math.max(x.abs, y.abs))
end
endOrigin.=~(a, b, rel_tol: c, abs_tol: d), or a binary operator without qualification if the defaults are sufficient: a =~ b. I'm not sure why the former requires qualification.
I think mayhbe my code is wrong and it is calling the wrong overload
No it is calling the same method in both cases.
I think everything is fine actually. If anyone has any suggestions for improvements on this snippet, I'd appreciate it: https://play.crystal-lang.org/#/r/bky9
save you 2 lines :p
I just found what I think is a very minor compiler bug