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<hightower2> well, I guess if one really wanted to do so, one could stick to a rule of always prefixing local vars with something, manually...
this way its always clear what is a method call and what isnt
however, a good usecase for using
self.x is if you have customer logic in the getter and/or are using a lazily initialized ivar
Oh, glossed over. lazy was already mentioned
Does crystal have anything like...I'm not sure what it's called, but in Nim, you can assign a slice to a slice of a variable...like:
var x = [1, 2, 3, 4, 5]
var y = [6, 7, 8, 9, 10]
x[1..2] = y[1..2] # x => [1, 7, 8, 4, 5]
Oh nice. It seems you can even grow shrink it with unsymmetrical ranges
Thanks @asterite
Yes :-) It's documented here: https://crystal-lang.org/api/1.1.0/Array.html#[]=(range:Range,values:Array(T))-instance-method
Are there functions for extracting the sign and fractional components of floating-point numbers? In some languages you have something like
sign and fract:sign(42.0) # 1.0
sign (-42.0) # -1.0
sign (0.0) # 0.0
fract(42.123) # 0.123
I suppose line 3 can be implemented differently if there is a distinction between IEEE-754 positive and negative zero
last one could just be like
value - (value.floor) probably?
If I have a type with value types (floats) for ivars, is it conventional to call a method which copies it
clone or dup? In this case there is nothing to traverse for a deep copy, but I see some projects use clone in this case, while others use dup, so I'm not sure if there is a consensus.
Maybe I worded it poorly. I was stating that either would be semantically correct for this particular example, and asking if there was a general agreement of which takes preference.
the real use case is to parse a
scope.yml having the properties roots, paths, etc. in a Scope class, I'd like to avoid flow control to check the filters as scope.roots, scope.paths, to something like scope.filters having their own class
I have
Scope with property roots and property paths to pull the data from the file, but what I want when creating the instance is more something like a property filters doing when having roots keys, Root.new(value), etc.
so when filtering, I can just do
scope.filters.all? { |filter| filter.evaluate_with(path) }
like
ScopeFile and using it to create the new Scope with the correct filters
that could do like
Item.new pull.read_string and return that array
I have to re-check if the props are nil, what they are supposed to do etc.
Just saw that you were using the old source in your dependencies
I'll fix the dependency URI.
Am I correct to assume that all optional parameters are also named? That is, there is no such thing as optional positional parameters in this language like I am used to? 😆