format() should accept SubString as well as String

[bluesmoon]

In format:

function format( x::T;
 width::Int=-1,
 precision::Int= -1,
 leftjustified::Bool=false,
 zeropadding::Bool=false, # when right-justified, use 0 instead of space to fill
 commas::Bool=false,
 signed::Bool=false, # +/- prefix
 positivespace::Bool=false,
 stripzeros::Bool=(precision== -1),
 parens::Bool=false, # use (1.00) instead of -1.00. Used in finance
 alternative::Bool=false, # usually for hex
 mixedfraction::Bool=false,
 mixedfractionsep::UTF8Str="_",
 fractionsep::UTF8Str="/", # num / den
 fractionwidth::Int = 0,
 tryden::Int = 0, # if 2 or higher,
 # try to use this denominator, without losing precision
 suffix::UTF8Str="", # useful for units/%
 autoscale::Symbol=:none, # :metric, :binary or :finance
 conversion::ASCIIStr=""
 ) where {T<:Real}

several of the parameters are either UTF8Str or ASCIIStr, but this fails when the parameter passed in is a SubString{T}. This seemed to work with Formatting.jl

[ScottPJones]

Thanks for finding this! Sorry I've been out of touch the last couple of months! Will look at fixing it now at JuliaCon