Merge pull request #79 from oscardssmith/patch-2

avoid overflow on `exp` and friends.

src/arithmetics.jl

@@ -19,13 +19,22 @@ for op in (:(+), :(-), :(*), :(/), :(^))
 end
 
 # ONE ARGUMENT ARITHMETIC, sqrt, exp, log, etc. via conversion
-for op in (:sqrt, :exp, :exp2, :exp10, :expm1, :log, :log2, :log10, :log1p,
+for op in (:sqrt, :cbrt, :log, :log2, :log10, :log1p,
             :sin, :cos, :tan, :sinpi, :cospi)
     @eval begin
         Base.$op(x::T) where {T<:AbstractPosit} = convert(T,$op(float(x)))
     end
 end
 
+for op in (:exp, :exp2, :exp10, :expm1)
+    @eval begin
+        function Base.$op(x::T) where {T<:AbstractPosit}
+            val = $op(float(x))
+            isinf(val) ? floatmax(T) : convert(T, val)
+        end
+    end
+end
+
 Base.sincos(x::AbstractPosit) = sin(x),cos(x)   # not in eval loop because of convert
 Base.sincospi(x::AbstractPosit) = sinpi(x),cospi(x)   # not in eval loop because of convert