Merge pull request #10 from jrevels/jr/warn

add flag to disable warnings

src/CommonSubexpressions.jl

@@ -24,7 +24,7 @@ disqualify!(cache::Cache, s::Symbol) = push!(cache.disqualified_symbols, s)
 disqualify!(cache::Cache, expr::Expr) = foreach(arg -> disqualify!(cache, arg), expr.args)
 
 # fallback for non-Expr arguments
-combine_subexprs!(setup, expr) = expr
+combine_subexprs!(setup, expr, warn_enabled::Bool) = expr
 
 const standard_expression_forms = Set{Symbol}(
     (:call,
@@ -49,31 +49,31 @@ const assignment_expression_forms = Set{Symbol}(
      :(*=),
      :(/=)))
 
-function combine_subexprs!(cache::Cache, expr::Expr)
+function combine_subexprs!(cache::Cache, expr::Expr, warn_enabled::Bool)
     if expr.head == :function
         # We can't continue CSE through a function definition, but we can
         # start over inside the body of the function:
         for i in 2:length(expr.args)
-            expr.args[i] = combine_subexprs!(expr.args[i])
+            expr.args[i] = combine_subexprs!(expr.args[i], warn_enabled)
         end
     elseif expr.head == :line
         # nothing
     elseif expr.head in assignment_expression_forms
         disqualify!(cache, expr.args[1])
         for i in 2:length(expr.args)
-            expr.args[i] = combine_subexprs!(cache, expr.args[i])
+            expr.args[i] = combine_subexprs!(cache, expr.args[i], warn_enabled)
         end
     elseif expr.head == :generator
         for i in vcat(2:length(expr.args), 1)
-            expr.args[i] = combine_subexprs!(cache, expr.args[i])
+            expr.args[i] = combine_subexprs!(cache, expr.args[i], warn_enabled)
         end
     elseif expr.head in standard_expression_forms
         for (i, child) in enumerate(expr.args)
-            expr.args[i] = combine_subexprs!(cache, child)
+            expr.args[i] = combine_subexprs!(cache, child, warn_enabled)
         end
         if expr.head == :call
             for (i, child) in enumerate(expr.args)
-                expr.args[i] = combine_subexprs!(cache, child)
+                expr.args[i] = combine_subexprs!(cache, child, warn_enabled)
             end
             if all(!isa(arg, Expr) && !(arg in cache.disqualified_symbols) for arg in expr.args)
                 combined_args = Symbol(expr.args...)
@@ -87,25 +87,25 @@ function combine_subexprs!(cache::Cache, expr::Expr)
             end
         end
     else
-        warn("CommonSubexpressions can't yet handle expressions of this form: $(expr.head)")
+        warn_enabled && warn("CommonSubexpressions can't yet handle expressions of this form: $(expr.head)")
     end
     return expr
 end
 
-combine_subexprs!(x) = x
+combine_subexprs!(x, warn_enabled::Bool = true) = x
 
-function combine_subexprs!(expr::Expr)
+function combine_subexprs!(expr::Expr, warn_enabled::Bool)
     cache = Cache()
-    expr = combine_subexprs!(cache, expr)
+    expr = combine_subexprs!(cache, expr, warn_enabled)
     Expr(:block, cache.setup..., expr)
 end
 
-macro cse(expr)
-    result = combine_subexprs!(expr)
+macro cse(expr, warn_enabled::Bool = true)
+    result = combine_subexprs!(expr, warn_enabled)
     # println(result)
     esc(result)
 end
 
-cse(expr) = combine_subexprs!(copy(expr))
+cse(expr, warn_enabled::Bool = true) = combine_subexprs!(copy(expr), warn_enabled)
 
 end