[julia-users] Why is the type of a variable different from inside and outside a let block?

[Ismael VC]

This was surprising:

julia> versioninfo()
Julia Version 0.4.0-dev+5491
Commit cb77503 (2015-06-21 09:45 UTC)
Platform Info:
  System: Linux (x86_64-unknown-linux-gnu)
  CPU: Intel(R) Xeon(R) CPU E5-2670 v2 @ 2.50GHz
  WORD_SIZE: 64
  BLAS: libopenblas (USE64BITINT DYNAMIC_ARCH NO_AFFINITY Sandybridge)
  LAPACK: libopenblas
  LIBM: libopenlibm
  LLVM: libLLVM-3.3

julia> let
       x::Float64 = 5
       end::Float64
ERROR: TypeError: typeassert: expected Float64, got Int64

julia> let
       x::UTF8String = "test"
       end::UTF8String
ERROR: TypeError: typeassert: expected UTF8String, got ASCIIString