Strange errors with ifelse

[simonster]

I ran into this while making #5811. It's silly (it's not actually a good idea to use ifelse here) but I don't think it should be doing what it was. The code is here. When the benchmark runs the first time, it works, but the second time, it reliably gives:

julia> reload("pathological_unique.jl")
ran once
ERROR: no method getindex(Array{Float64,2}, Array{Any,1}, Range1{Int64})
 in unique at /home/simon/Desktop/pathological_unique.jl:25
 in reload_path at loading.jl:144
 in reload at loading.jl:77
while loading /home/simon/Desktop/pathological_unique.jl, in expression starting on line 35

If I keep reloading the file at the REPL, I keep getting errors:

julia> reload("pathological_unique.jl")
ran once
ERROR: no method getindex(
 in unique at /home/simon/Desktop/pathological_unique.jl:25
 in reload_path at loading.jl:144
 in reload at loading.jl:77SYSTEM: show(lasterr) caused an error
ERROR: no method Enumerate{I}((Array{Float64,2},Array{Any,1},Range1{Int64}))
 in showerror at repl.jl:108
 in showerror at repl.jl:63
 in showerror at repl.jl:71
 in anonymous at client.jl:93
 in with_output_color at util.jl:441
 in display_error at client.jl:91

julia> reload("pathological_unique.jl")
ERROR: no method getindex(
 in unique at /home/simon/Desktop/pathological_unique.jl:25
 in reload_path at loading.jl:144
 in reload at loading.jl:77SYSTEM: show(lasterr) caused an error
ERROR: no method Enumerate{I}(
 in showerror at repl.jl:108
 in showerror at repl.jl:63
 in showerror at repl.jl:71
 in anonymous at client.jl:93
 in with_output_color at util.jl:441
 in display_error at client.jl:91SYSTEM: show(lasterr) caused an error
WARNING: it is likely that something important is broken, and Julia will not be able to continue normally

versioninfo is:

julia> versioninfo()
Julia Version 0.3.0-prerelease+1561
Commit d15ce97* (2014-02-13 16:38 UTC)
Platform Info:
  System: Linux (x86_64-linux-gnu)
  CPU: Intel(R) Core(TM) i7-3930K CPU @ 3.20GHz
  WORD_SIZE: 64
  BLAS: libopenblas (USE64BITINT DYNAMIC_ARCH NO_AFFINITY)
  LAPACK: libopenblas
  LIBM: libopenlibm

I can't reproduce this on OS X on my MacBook Pro.