add fld, mod, div, rem setters

Project.toml

@@ -1,7 +1,7 @@
 name = "Accessors"
 uuid = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
 authors = ["Takafumi Arakaki <[email protected]>", "Jan Weidner <[email protected]> and contributors"]
-version = "0.1.20"
+version = "0.1.21"
 
 [deps]
 Compat = "34da2185-b29b-5c13-b0c7-acf172513d20"

src/functionlenses.jl

@@ -53,7 +53,11 @@ set(x,     ::typeof(imag), y) = real(x) + im*y
 set(x,    ::typeof(angle), y) = abs(x) * cis(y)
 set(x,      ::typeof(abs), y) = y >= zero(y) ? y * sign(x) : throw(DomainError(y, "cannot set abs($x) to $y"))
 
-set(x, ::typeof(mod2pi), y) = 0 <= y <= 2π ? 2π * fld(x, 2π) + y : throw(DomainError(y, "cannot set mod2pi"))
+set(x, ::typeof(mod2pi), y) = set(x, @optic(mod(_, 2π)), y)
+set(x, f::Base.Fix2{typeof(fld)}, y) = set(x, @optic(first(fldmod(_, f.x))), y)
+set(x, f::Base.Fix2{typeof(mod)}, y) = set(x, @optic(last(fldmod(_, f.x))), y)
+set(x, f::Base.Fix2{typeof(div)}, y) = set(x, @optic(first(divrem(_, f.x))), y)
+set(x, f::Base.Fix2{typeof(rem)}, y) = set(x, @optic(last(divrem(_, f.x))), y)
 
 set(arr, ::typeof(normalize), val) = norm(arr) * val
 set(arr, ::typeof(norm), val)      = val/norm(arr) * arr # should we check val is positive?

test/test_functionlenses.jl

@@ -95,14 +95,19 @@ end
     @test 1.0 + 2im === @set imag(1+1im) = 2.0
     @test 1u"m"         === @set real(2u"m") = 1u"m"
     @test (2 + 1im)u"m" === @set imag(2u"m") = 1u"m"
+
+    @test set.(10, @optic(mod(_, 3)), 0:2) == 9:11
+    @test_throws DomainError set(10, @optic(mod(_, 3)), 10)
 
     test_getset_laws(mod2pi, 5.3, 1, 2; cmp=isapprox)
     test_getset_laws(mod2pi, -5.3, 1, 2; cmp=isapprox)
 
     test_getset_laws(!, true, true, false)
     @testset for o in [
             # invertible lenses below: no need for extensive testing, simply forwarded to InverseFunctions
-            inv, +, exp, sqrt, @optic(2 + _), @optic(_ * 3), @optic(log(2, _))
+            inv, +, exp, sqrt, @optic(2 + _), @optic(_ * 3), @optic(log(2, _)),
+            # non-invertible lenses, indirectly forwarded to InverseFunctions
+            @optic(mod(_, 21)), @optic(fld(_, 3)), @optic(rem(_, 21)), @optic(div(_, 3)),
         ]
         x = 5
         test_getset_laws(o, x, 10, 20; cmp=isapprox)