Improve type stability

Author: mtfishman

src/MatrixAlgebra.jl

@@ -76,13 +76,32 @@ for (svd, svd_trunc, svd_full, svd_compact) in (
         (:svd!, :svd_trunc!, :svd_full!, :svd_compact!),
     )
     @eval begin
-        function $svd(A::AbstractMatrix; full::Bool = false, trunc = nothing, kwargs...)
-            return if !isnothing(trunc)
-                @assert !full "Specified both full and truncation, currently not supported"
-                $svd_trunc(A; trunc, kwargs...)
-            else
-                (full ? $svd_full : $svd_compact)(A; kwargs...)
-            end
+        function $svd(
+                A::AbstractMatrix;
+                full::Union{Bool, Val{Bool}} = Val(false),
+                trunc = nothing,
+                kwargs...,
+            )
+            return _svd(full, trunc, A; kwargs...)
+        end
+        function _svd(full::Bool, trunc, A::AbstractMatrix; kwargs...)
+            return _svd(Val(full), trunc, A; kwargs...)
+        end
+        function _svd(full::Val{false}, trunc::Nothing, A::AbstractMatrix; kwargs...)
+            return $svd_compact(A; kwargs...)
+        end
+        function _svd(full::Val{false}, trunc, A::AbstractMatrix; kwargs...)
+            return $svd_trunc(A; trunc, kwargs...)
+        end
+        function _svd(full::Val{true}, trunc::Nothing, A::AbstractMatrix; kwargs...)
+            return $svd_full(A; kwargs...)
+        end
+        function _svd(full::Val{true}, trunc, A::AbstractMatrix; kwargs...)
+            return throw(
+                ArgumentError(
+                    "Specified both full and truncation, currently not supported"
+                )
+            )
         end
     end
 end

test/test_factorizations.jl

@@ -148,26 +148,26 @@ end
     labels_Vᴴ = (:d, :c)
 
     Acopy = deepcopy(A)
-    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_U, labels_Vᴴ; full = true)
+    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_U, labels_Vᴴ; full = Val(true))
     @test A == Acopy # should not have altered initial array
     US, labels_US = contract(U, (labels_U..., :u), S, (:u, :v))
     A′ = contract(labels_A, US, labels_US, Vᴴ, (:v, labels_Vᴴ...))
     @test A ≈ A′
     @test size(U, 1) * size(U, 2) == size(U, 3) # U is unitary
     @test size(Vᴴ, 1) == size(Vᴴ, 2) * size(Vᴴ, 3) # V is unitary
 
-    U, S, Vᴴ = svd(A, (2, 1), (4, 3); full = true)
+    U, S, Vᴴ = svd(A, (2, 1), (4, 3); full = Val(true))
     US, labels_US = contract(U, (labels_U..., :u), S, (:u, :v))
     @test A ≈ contract(labels_A, US, labels_US, Vᴴ, (:v, labels_Vᴴ...))
 
-    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_A, (); full = true)
+    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_A, (); full = Val(true))
     @test A == Acopy # should not have altered initial array
     US, labels_US = contract(U, (labels_A..., :u), S, (:u, :v))
     A′ = contract(labels_A, US, labels_US, Vᴴ, (:v,))
     @test A ≈ A′
     @test size(Vᴴ, 1) == 1
 
-    U, S, Vᴴ = @constinferred svd(A, labels_A, (), labels_A; full = true)
+    U, S, Vᴴ = @constinferred svd(A, labels_A, (), labels_A; full = Val(true))
     @test A == Acopy # should not have altered initial array
     US, labels_US = contract(U, (:u,), S, (:u, :v))
     A′ = contract(labels_A, US, labels_US, Vᴴ, (:v, labels_A...))
@@ -182,7 +182,7 @@ end
     labels_Vᴴ = (:d, :c)
 
     Acopy = deepcopy(A)
-    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_U, labels_Vᴴ; full = false)
+    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_U, labels_Vᴴ; full = Val(false))
     @test A == Acopy # should not have altered initial array
     US, labels_US = contract(U, (labels_U..., :u), S, (:u, :v))
     A′ = contract(labels_A, US, labels_US, Vᴴ, (:v, labels_Vᴴ...))
@@ -193,14 +193,14 @@ end
     Svals = @constinferred svdvals(A, labels_A, labels_U, labels_Vᴴ)
     @test Svals ≈ diag(S)
 
-    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_A, (); full = false)
+    U, S, Vᴴ = @constinferred svd(A, labels_A, labels_A, (); full = Val(false))
     @test A == Acopy # should not have altered initial array
     US, labels_US = contract(U, (labels_A..., :u), S, (:u, :v))
     A′ = contract(labels_A, US, labels_US, Vᴴ, (:v,))
     @test A ≈ A′
     @test size(U, ndims(U)) == 1 == size(Vᴴ, 1)
 
-    U, S, Vᴴ = @constinferred svd(A, labels_A, (), labels_A; full = false)
+    U, S, Vᴴ = @constinferred svd(A, labels_A, (), labels_A; full = Val(false))
     @test A == Acopy # should not have altered initial array
     US, labels_US = contract(U, (:u,), S, (:u, :v))
     A′ = contract(labels_A, US, labels_US, Vᴴ, (:v, labels_A...))