sym: handy macro mx.var for creating mx.Variable (#338)

dmlc · Nov 22, 2017 · f126482 · f126482
1 parent 91a410e
commit f126482
Show file tree

Hide file tree

Showing 3 changed files with 47 additions and 0 deletions.
diff --git a/NEWS.md b/NEWS.md
@@ -6,6 +6,16 @@
 
 * `mx.get_children` for exploring the graph programmatically. (#TBD)
 
+* A handy macro `@mx.var` for creating `mx.Variable`. (#TBD)
+
+  ```julia
+  julia> x = @mx.var x
+  MXNet.mx.SymbolicNode x
+
+  julia> x, y, z = @mx.var x y z
+  (MXNet.mx.SymbolicNode x, MXNet.mx.SymbolicNode y, MXNet.mx.SymbolicNode z)
+  ```
+
 # v0.3.0 (2017.11.16)
 
 * Update `libmxnet` to

diff --git a/src/symbolic-node.jl b/src/symbolic-node.jl
@@ -347,6 +347,27 @@ function Variable(name :: Union{Symbol, AbstractString}; attrs = Dict())
   node
 end
 
+"""
+    @var <symbols>...
+
+A handy macro for creating `mx.Variable`.
+
+```julia
+julia> x = @mx.var x
+MXNet.mx.SymbolicNode x
+
+julia> x, y, z = @mx.var x y z
+(MXNet.mx.SymbolicNode x, MXNet.mx.SymbolicNode y, MXNet.mx.SymbolicNode z)
+```
+"""
+macro var(n::Symbol)
+  Expr(:call, :Variable, QuoteNode(n))
+end
+
+macro var(names::Symbol...)
+  Expr(:tuple, map(n -> Expr(:call, :Variable, QuoteNode(n)), names)...)
+end
+
 """
     Group(nodes :: SymbolicNode...)
 

diff --git a/test/unittest/symbolic-node.jl b/test/unittest/symbolic-node.jl
@@ -506,6 +506,21 @@ function test_get_name()
   @test contains(name, "Ptr")
 end  # function test_get_name
 
+function test_var()
+  info("SymbolicNode::var")
+  x = @mx.var x
+  @test x isa mx.SymbolicNode
+
+  x′ = @mx.var x
+  @test x.handle != x′.handle
+
+  x, y, z = @mx.var x y z
+  @test x isa mx.SymbolicNode
+  @test y isa mx.SymbolicNode
+  @test z isa mx.SymbolicNode
+end  # test_var
+
+
 ################################################################################
 # Run tests
 ################################################################################
@@ -529,6 +544,7 @@ end  # function test_get_name
   test_div()
   test_power()
   test_get_name()
+  test_var()
 end
 
 end