Fix 0.6 typealias depwarn (#103)

Author: yuyichao

src/Calculus.jl

@@ -24,7 +24,7 @@ module Calculus
     # abstract type GradientEstimator end
     # abstract type HessianEstimator end
 
-    # typealias NonDifferentiableFunction Function
+    # const NonDifferentiableFunction = Function
     # type DifferentiableFunction
     #   f::Function
     #   g::Function

src/symbolic.jl

@@ -14,7 +14,7 @@ import Base.show, Base.(==)
 
 Compat.@compat abstract type Symbolic end
 Compat.@compat abstract type AbstractVariable <: Symbolic end
-Compat.@compat typealias SymbolicVariable Union{Symbol, AbstractVariable}
+const SymbolicVariable = Union{Symbol, AbstractVariable}
 
 
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