Dict(kw...)

[jw3126]

A common pattern is converting keyword arguments into a Dict for easier manipulation. On master this currently throws an error:

julia> f(;kw...) = Dict(kw...)
f (generic function with 1 method)

julia> f(a=1)
ERROR: ArgumentError: Dict(kv): kv needs to be an iterator of tuples or pairs
Stacktrace:
 [1] Dict(::Int64) at ./dict.jl:147
 [2] #f#1 at ./REPL[1]:1 [inlined]
 [3] (::getfield(, Symbol("#kw##f")))(::NamedTuple{(:a,),Tuple{Int64}}, ::typeof(f)) at ./<missing>:0
 [4] top-level scope

I think a depwarn would be better. Especially for code that needs to work on v0.6 and master.

[fredrikekre]

See #25179, you can use f(;kw...) = Dict(pairs(kw)) and f(;kw...) = Dict(Compat.pairs(kw)) on 0.6

[jw3126]

Thanks! Is there a reason other then lack of time for this having no depwarn?

[jw3126]

I am often in the situation that I have a package want to quickly try a feature on master. In this case I don't care if my package (or dependencies!) throw tons of depwarns, but an error is a problem. Thats why I would prefer a depwarn.

[JeffBezanson]

kw will now support many dict operations, so it's possible a Dict is not needed anymore. Out of curiosity, what do you need the Dict for? (It doesn't negate the issue of course, just wondering about use cases.)

[JeffBezanson]

Also duplicate of #25177

[jw3126]

I don't specifically need a Dict, just things like kw[:some_option]. And in v0.6 doing Dict(kw...) is a common trick to achieve this.

[JeffBezanson]

kw[:some_option] should work now, as well as kw.some_option.