Changed Expr args for :(:) in 0.7?

Internals & Design
1

In Julia v0.6:

julia> :(2:34) |> dump
Expr
  head: Symbol :
  args: Array{Any}((2,))
    1: Int64 2
    2: Int64 34
  typ: Any

In Julia v0.7

julia> :(2:34) |> dump
Expr
  head: Symbol call
  args: Array{Any}((3,))
    1: Symbol :
    2: Int64 2
    3: Int64 34
  typ: Any

Is this intended behavior? Why is has it changed? The :(:) symbol now appears in the args list, this is unexpected behavior and made my code misbehave. Are there any more of these type of changes?

2

Yes, this is an intended breaking change. It makes : much more like the other infix operators. See https://github.com/JuliaLang/julia/pull/25957 for more details (it got committed in https://github.com/JuliaLang/julia/pull/26074, but the former PR has more details and motivation).

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3

Also,

using MacroTools
@capture :(2:34) a_:b_ 
(a, b) # (2, 34)

works for me in both v0.6 and v0.7, if you want to unify code for both versions.

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