create package from existing code

src/free_groups.jl

@@ -0,0 +1,22 @@
+import Base:convert
+
+export FGSymbol, FGWord
+
+immutable FGSymbol <: GSymbol
+    gen::String
+    pow::Int
+end
+
+(==)(s::FGSymbol, t::FGSymbol) = s.gen == t.gen && s.pow == t.pow
+hash(s::FGSymbol, h::UInt) = hash(s.gen, hash(s.pow, hash(:FGSymbol, h)))
+
+IdSymbol(::Type{FGSymbol}) = FGSymbol("(id)", 0)
+FGSymbol(x::String) = FGSymbol(x,1)
+
+inv(s::FGSymbol) = FGSymbol(s.gen, -s.pow)
+convert(::Type{FGSymbol}, x::String) = FGSymbol(x)
+change_pow(s::FGSymbol, n::Int) = (n==0 ? i=one(s) : FGSymbol(s.gen, n))
+
+typealias FGWord GWord{FGSymbol}
+
+FGWord(s::FGSymbol) = FGWord([s])