diff --git a/REQUIRE b/REQUIRE
index c069e29..fa89aa4 100644
--- a/REQUIRE
+++ b/REQUIRE
@@ -1,3 +1,2 @@
-julia 0.6
+julia 0.7
 Combinatorics
-Compat 0.34
diff --git a/appveyor.yml b/appveyor.yml
index f0f7d95..c541de9 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -7,7 +7,6 @@ environment:
 
 matrix:
   allow_failures:
-  - JULIA_URL: "https://julialang-s3.julialang.org/bin/winnt/x86/0.7/julia-0.7-latest-win32.exe"
   - JULIA_URL: "https://julialangnightlies-s3.julialang.org/bin/winnt/x86/julia-latest-win32.exe"
   - JULIA_URL: "https://julialangnightlies-s3.julialang.org/bin/winnt/x64/julia-latest-win64.exe"
 
diff --git a/src/Dendriform.jl b/src/Dendriform.jl
index dbb5cca..c91753f 100644
--- a/src/Dendriform.jl
+++ b/src/Dendriform.jl
@@ -4,7 +4,7 @@ module Dendriform
 # This file is part of Dendriform.jl. It is licensed under the GPL license
 # Dendriform Copyright (C) 2017 Michael Reed
 
-using Combinatorics, Compat
+using Combinatorics
 
 export PBTree, Grove, GroveBin, ==, Cn, grovesort, grovesort!, σ, print, grovecomposition, grovedisplay
 
@@ -125,6 +125,7 @@ Grove(d::UI8I) = convert(Grove,d)
 Grove(d::UI8I,s::BitArray{1}) = TreeLoday(d,s)
 Grove(g::GroveBin) = convert(Grove,g)
 Grove(s::BitArray{1}) = Grove(CnInv(length(s)),s)
+Grove(g::Grove) = g
 
 """
     Grove(degree::Int, index::Integer)
@@ -242,7 +243,7 @@ function GroveExtend!(Y::Array{Grove,1},R::Array{Array{Int,1},1},deg::UInt8)
         # initialize total grove
         Yn = Grove(Array{UInt8,2}(undef,Cn(n),n))
         # loop over left-branch grove
-        n==1 ? (Yn.Y[τ,1] .= n) : (Yn.Y[τ:lYn,n] .= n)
+        n==1 ? (Yn.Y[τ,1] = n) : (Yn.Y[τ:lYn,n] .= n)
         for λ ∈ 1:lYn
             Yn.Y[τ,1:n-1] = Y[n].Y[λ,:]
             τ += 1
diff --git a/src/morphism.jl b/src/morphism.jl
index e06cbcd..35673f1 100644
--- a/src/morphism.jl
+++ b/src/morphism.jl
@@ -108,7 +108,7 @@ grovebit(g::Union{Ar1UI8I,Ar2UI8I}) = grovebit(Grove(g))
 grovebit(g::GroveBin) = grovebit(g.degr,g.gbin)
 
 function grovebit(d::UI8I,s::Integer)
-    gb = '1' .== reverse(collect(string(s,base=2)),dims=1)
+    gb = Ref('1') .== reverse(collect(string(s,base=2)),dims=1)
     return vcat(gb,falses(Cn(d)-length(gb)))
 end
 
@@ -128,7 +128,7 @@ function groveindex(d::UI8I,l::Int,g::Ar2UI8I)
             s += BigInt(2)^(findfirst(v.==gt[c])-1)
         end
     catch
-        treecheck(g) ? throw(DomainError()) : s=BigInt(-1)
+        treecheck(g) ? throw(DomainError(g)) : s=BigInt(-1)
     end
     return s
 end
@@ -193,7 +193,7 @@ TreeLoday(d::UI8I,s::Integer) = Grove(d,s)
 
 Returns BaseTree objects for any AbstractGrove
 """
-TreeBase(d::UI8I,s::Integer) = TreeBase(d,grovebit(findall(s)))
+TreeBase(d::UI8I,s::Integer) = TreeBase(d,grovebit(findall(x->x!=0,s)))
 
 function TreeBase(d::UI8I,ind::BitArray) # from treeindex
     y = Υ(d).Y
@@ -317,7 +317,7 @@ function TreeRational(d::UI8I,indb::BitArray) # from treeindex
 end
 
 TreeRational(μ::BaseTree) = (s=treeshift(); s+((-1)^s)*ΘInt(μ.μ)//ΘMax(length(μ.μ)))
-TreeRational(deg::UI8I,Θ::Array{Int,1}) = (s=treeshift(); 1-s-((-1)^s)*Θ.//ΘMax(deg))
+TreeRational(deg::UI8I,Θ::Array{Int,1}) = (s=treeshift(); 1-s.-((-1)^s)*Θ.//ΘMax(deg))
 
 function TreeRational(Y::Array{BaseTree,1})
     γ = length(Y)
diff --git a/src/poset.jl b/src/poset.jl
index 27b0d97..5e44777 100644
--- a/src/poset.jl
+++ b/src/poset.jl
@@ -226,7 +226,7 @@ function intcomp(d::Int)
         for i ∈ 1:Int(groveindex(Grove(q))), j ∈ 1:Int(groveindex(Grove(d-q)))
             z = GroveBin(Grove(q,i) + Grove(d-q,j))
             f = findall(s->s==z.gbin, ins)
-            length(f) == 0 ? (cn += 1) : (cc[f] += 1)
+            length(f) == 0 ? (cn += 1) : (cc[f] .+= 1)
         end
     end
     @info "Non-intervals: $cn"
@@ -242,7 +242,7 @@ function intcompt(d::Int)
         for i ∈ 1:Int(Cn(q)), j ∈ 1:Int(Cn(d-q))
             z = GroveBin(PBTree(q,i) + PBTree(d-q,j))
             f = findall(s->s==z.gbin, ins)
-            length(f) == 0 ? (cn += 1) : (cc[f] += 1)
+            length(f) == 0 ? (cn += 1) : (cc[f] .+= 1)
         end
     end
     #@info "Non-intervals: $cn"
diff --git a/test/runtests.jl b/test/runtests.jl
index 07834f4..ea5bfb4 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1,5 +1,4 @@
-using Dendriform
-using Test
+using Dendriform, Test
 import Dendriform: GroveError, TreeInteger, TreeRational, TreeBase, TreeLoday
 
 d = 5
@@ -22,7 +21,7 @@ d = 5
 @test Grove(d) |> grovesort! == Grove(d) == Grove(d,2^Cn(d)-1)
 @test Grove(d) == d |> TreeBase |> TreeLoday
 @test (k = Grove(d) |> TreeBase |> TreeLoday; k == k |> TreeBase |> TreeLoday)
-@test TreeLoday(0,Array{Int,1}(0)) == Grove(0)
+@test TreeLoday(0,Array{Int,1}(undef,0)) == Grove(0)
 @test [TreeBase([1:d...])] == TreeBase(d,1)
 @test Grove(d) |> TreeBase |> TreeInteger == Grove(d) |> TreeInteger
 @test (grovesort(false); TreeLoday(d,treeindex(Grove(d))) == Grove(d))