using PyCall not working in Julia 0.4 master

[waterswims]

Hey just installed a fresh lubuntu distro and was installing my things and checking they are working, installed julia 0.4 and tried it and got this error

julia> using PyCall
ERROR: LoadError: LoadError: MethodError: convert has no method matching convert(::Type{Ptr{UInt8}}, ::ASCIIString)
This may have arisen from a call to the constructor Ptr{UInt8}(...),
since type constructors fall back to convert methods.
Closest candidates are:
convert{T}(::Type{Ptr{T}}, ::UInt64)
convert{T}(::Type{Ptr{T}}, ::Int64)
convert{T}(::Type{Ptr{T}}, ::Ptr{T})
...

in call at /home/jmw2g14/.julia/v0.4/PyCall/src/pytype.jl:92
in include at ./boot.jl:250
in include_from_node1 at ./loading.jl:128
in include at ./boot.jl:250
in include_from_node1 at ./loading.jl:128
in reload_path at ./loading.jl:152
in _require at ./loading.jl:67
in require at ./loading.jl:51

My julia version is 0.4.0-dev+3718

[stevengj]

Yes, they just merged a patch in "0.4" (i.e. git master) that broke everything (JuliaLang/julia#9986?).... you really should use Julia 0.3 unless you are hacking on Julia itself, or are keen to be on the bleeding edge. If you want to work from git, checkout the release-0.3 branch rather than master.

cc: @vtjnash, shouldn't we have deprecated these convert methods rather than removing them? I'm confused: how are you supposed to pass ByteString arguments to C in Julia 0.4 if not as Ptr{UInt8}?

[vtjnash]

we can probably add back a deprecation warning for them. all methods that convert to Ptr were moved to unsafe_convert as a warning that the user must not let the argument become inaccessible to the julia runtime. inside ccall, you can just pass the ByteString and let convert get called for you.

looking through that code, it would be cleaner/faster to just have gstring_ptr push the string to a global const array, rather than gensym'ing and eval'ing a constant variable to remember it. also, it looks like pyjlwrap_members is creating a compile-time pointer to the pyjlwrap_membername string