Define a static type variable is too Verbose

General Usage
8

I think doing it at the time when the variable was defined, like initially requested, is the easy solution:

"""
    @var x = rhs

Define `x` to be of fixed type, the type of `rhs`, and assign `rhs` to it.
"""
macro var(ex)
    if !(ex isa Expr && ex.head == :(=))
        throw(ArgumentError("expression should be of the form `var = value`"))
    end
    name = ex.args[1]
    rhs = ex.args[2]
    tmp = gensym(name)
    esc(quote
        $tmp = $rhs
        ($name)::typeof($tmp) = $tmp
    end)
end

Test

julia> function f(x)
           @var y = x
           y = 1.2
           return y
           end
f (generic function with 1 method)

julia> f(1)
ERROR: InexactError: Int64(1.2)
Stacktrace:
 [1] Type at ./float.jl:703 [inlined]
 [2] convert(::Type{Int64}, ::Float64) at ./number.jl:7
 [3] f(::Int64) at ./REPL[2]:3
 [4] top-level scope at REPL[3]:1

julia> f(1.3)
1.2
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