improve inference in Ray (#165)

* improve inference in Ray

* fix test on v1.6

Author: jishnub

Project.toml

@@ -1,6 +1,6 @@
 name = "ApproxFunOrthogonalPolynomials"
 uuid = "b70543e2-c0d9-56b8-a290-0d4d6d4de211"
-version = "0.5.21"
+version = "0.5.22"
 
 [deps]
 ApproxFunBase = "fbd15aa5-315a-5a7d-a8a4-24992e37be05"

src/Domains/Ray.jl

@@ -25,8 +25,20 @@ Ray{a}() where {a} = Ray{a,Float64}()
 angle(d::Ray{a}) where {a} = a*π
 
 # ensure the angle is always in (-1,1]
-Ray(c,a,L,o) = Ray{a==0 ? false : (abs(a)≈(1.0π) ? true : mod(a/π-1,-2)+1),typeof(c)}(c,L,o)
-Ray(c,a,o) = Ray{a==0 ? false : (abs(a)≈(1.0π) ? true : mod(a/π-1,-2)+1),typeof(c)}(c,one(typeof(c)),o)
+@inline function _Ray(c,a,L,o)
+    angle = if iszero(a)
+        false
+    else
+        (abs(a)≈(1.0π) ? true : mod(a/π-1,-2)+1)
+    end
+    Ray{angle,typeof(c)}(c,L,o)
+end
+@static if VERSION >= v"1.8"
+    Base.@constprop :aggressive Ray(c,a,L,o) = _Ray(c,a,L,o)
+else
+    Ray(c,a,L,o) = _Ray(c,a,L,o)
+end
+Ray(c,a,o) = Ray(c,a,one(typeof(c)),o)
 Ray(c,a) = Ray(c,a,one(typeof(c)),true)
 
 Ray() = Ray{false}()
@@ -35,14 +47,17 @@ Ray() = Ray{false}()
 
 ##deal with vector
 
+_rayangle(x) = angle(x)
+_rayangle(x::Real) = 0
+
 function convert(::Type{Ray}, d::AbstractInterval)
     a,b = endpoints(d)
     @assert abs(a)==Inf || abs(b)==Inf
 
     if abs(b)==Inf
-        Ray(a,angle(b),one(typeof(a)),true)
+        Ray(a,_rayangle(b),one(typeof(a)),true)
     else #abs(a)==Inf
-        Ray(b,angle(a),one(typeof(a)),false)
+        Ray(b,_rayangle(a),one(typeof(a)),false)
     end
 end
 Ray(d::AbstractInterval) = strictconvert(Ray, d)

test/LaguerreTest.jl

@@ -6,9 +6,15 @@ using ApproxFunBaseTest: testbandedoperator
 
 
 @verbose @testset "Laguerre and WeightedLaguerre" begin
-
+    @testset "Ray" begin
+        r = VERSION >= v"1.8" ? @inferred(Ray(0..Inf)) : Ray(0..Inf)
+        L = Laguerre(1.0,r)
+        f = x -> exp.(-x)
+        F = Fun(f, L)
+        @test F(.3) ≈ -F'(.3)
+    end
     @testset "General scaled rays" begin
-        r = Ray(-1.0,0.0,2.0,true)
+        r = @inferred (() -> Ray(-1.0,0.0,2.0,true))()
         L = Laguerre(1.0,r)
         f = x -> exp.(-x)
         F = Fun(f, L)