implement digits(T, n, base, pad); allow base == typemax(T) + 1

base/docs/helpdb.jl

@@ -4256,9 +4256,9 @@ Return a list of immediate subtypes of DataType `T`. Note that all currently loa
 subtypes
 
 doc"""
-    digits(n, [base], [pad])
+    digits([T], n, [base], [pad])
 
-Returns an array of the digits of `n` in the given base, optionally padded with zeros to a specified size. More significant digits are at higher indexes, such that `n == sum([digits[k]*base^(k-1) for k=1:length(digits)])`.
+Returns an array with element type `T` (default `Int`) of the digits of `n` in the given base, optionally padded with zeros to a specified size. More significant digits are at higher indexes, such that `n == sum([digits[k]*base^(k-1) for k=1:length(digits)])`.
 """
 digits
 

base/intfuncs.jl

@@ -308,16 +308,16 @@ bits(x::Union{Char,Int32,UInt32,Float32}) = bin(reinterpret(UInt32,x),32)
 bits(x::Union{Int64,UInt64,Float64})      = bin(reinterpret(UInt64,x),64)
 bits(x::Union{Int128,UInt128})            = bin(reinterpret(UInt128,x),128)
 
-function digits{T<:Integer}(n::Integer, base::T=10, pad::Integer=1)
+digits{T<:Integer}(n::Integer, base::T=10, pad::Integer=1) = digits(T, n, base, pad)
+
+function digits{T<:Integer}(::Type{T}, n::Integer, base::Integer=10, pad::Integer=1)
     2 <= base || throw(ArgumentError("base must be ≥ 2, got $base"))
-    m = max(pad,ndigits0z(n,base))
-    a = zeros(T,m)
-    digits!(a, n, base)
-    return a
+    digits!(zeros(T, max(pad, ndigits0z(n,base))), n, base)
 end
 
-function digits!{T<:Integer}(a::AbstractArray{T,1}, n::Integer, base::T=10)
+function digits!{T<:Integer}(a::AbstractArray{T,1}, n::Integer, base::Integer=10)
     2 <= base || throw(ArgumentError("base must be ≥ 2, got $base"))
+    base - 1 <= typemax(T) || throw(ArgumentError("type $T too small for base $base"))
     for i = 1:length(a)
         a[i] = rem(n, base)
         n = div(n, base)