Add @with_kwargs macro which automatically splats default_kwargs into a function call.

Author: Jack Dunham

src/solvers/default_kwargs.jl

@@ -96,3 +96,20 @@ function default_kwargs_macro(function_def)
 
   return rv
 end
+
+macro with_defaults(call_expr)
+  if @capture(call_expr, (func_(args__; kwargs__)) | (func_(args__)))
+    if isnothing(kwargs)
+      kwargs = []
+    end
+    rv = quote
+      $(esc(func))(
+        $(esc.(args)...);
+        default_kwargs($(esc(func)), $(esc.(args)...); $(esc.(kwargs)...))...,
+      )
+    end
+    return rv
+  else
+    throw(ArgumentError("unable to parse function call expression, try including brackets in the macro call."))
+  end
+end

test/solvers/test_default_kwargs.jl

@@ -1,5 +1,5 @@
 using Test: @test, @testset
-using ITensorNetworks: AbstractProblem, default_kwargs, RegionIterator, problem, region_kwargs
+using ITensorNetworks: AbstractProblem, default_kwargs, RegionIterator, problem, region_kwargs, @with_defaults
 
 module KwargsTestModule
 
@@ -37,4 +37,11 @@ end # KwargsTestModule
   @test KwargsTestModule.test_function(problem(our_iter); default_kwargs(KwargsTestModule.test_function, problem(our_iter); kw...)...) == (true, 1)
   @test KwargsTestModule.test_function(problem(not_our_iter); default_kwargs(KwargsTestModule.test_function, problem(not_our_iter); kw_not...)...) == (false, 2)
 
+  @test @with_defaults(KwargsTestModule.test_function(problem(our_iter))) == (true, 0)
+  @test @with_defaults(KwargsTestModule.test_function(problem(our_iter);)) == (true, 0)
+  @test @with_defaults(KwargsTestModule.test_function(problem(our_iter); bool = false)) == (false, 0)
+
+  let testval = @with_defaults KwargsTestModule.test_function(problem(our_iter); int = 3)
+    @test testval == (true, 3)
+  end
 end