Remove to_symbolic

Author: YingboMa

src/ModelingToolkit.jl

@@ -23,7 +23,7 @@ RuntimeGeneratedFunctions.init(@__MODULE__)
 using RecursiveArrayTools
 
 import SymbolicUtils
-import SymbolicUtils: Term, Add, Mul, Pow, Sym, to_symbolic, FnType,
+import SymbolicUtils: Term, Add, Mul, Pow, Sym, FnType,
                       @rule, Rewriters, substitute, similarterm,
                       promote_symtype
 
@@ -55,8 +55,6 @@ value(x) = x
 value(x::Num) = x.val
 
 
-using SymbolicUtils: to_symbolic
-SymbolicUtils.to_symbolic(n::Num) = value(n)
 SymbolicUtils.@number_methods(Num,
                               Num(f(value(a))),
                               Num(f(value(a), value(b))))

src/build_function.jl

@@ -93,7 +93,7 @@ function unflatten_long_ops(op, N=4)
     rule2 = @rule((*)((~~x)) => length(~~x) > N ?
                  *(*((~~x)[1:N]...) * (*)((~~x)[N+1:end]...)) : nothing)
 
-    op = to_symbolic(op)
+    op = value(op)
     Rewriters.Fixpoint(Rewriters.Postwalk(Rewriters.Chain([rule1, rule2])))(op)
 end
 

src/utils.jl

@@ -141,7 +141,7 @@ substitute(expr, s::Vector; kw...) = substituter(s)(expr; kw...)
 
 substituter(pair::Pair) = substituter((pair,))
 function substituter(pairs)
-    dict = Dict(to_symbolic(k) => to_symbolic(v)  for (k, v) in pairs)
+    dict = Dict(value(k) => value(v)  for (k, v) in pairs)
     (expr; kw...) -> SymbolicUtils.substitute(expr, dict; kw...)
 end
 

test/simplify.jl

@@ -1,4 +1,5 @@
 using ModelingToolkit
+using ModelingToolkit: value
 using Test
 
 @parameters t
@@ -34,11 +35,11 @@ d3 = Differential(x)(d2)
 @test ModelingToolkit.substitute(2x + y == 1, Dict(x => 0.0, y => 1.0)) === true
 
 # 699
-using SymbolicUtils: to_symbolic, substitute
+using SymbolicUtils: value, substitute
 @parameters t a(t) b(t)
 
 # back and forth substitution does not work for parameters with dependencies
-term = to_symbolic(a)
+term = value(a)
 term2 = substitute(term, a=>b)
 @test term2 isa Term{ModelingToolkit.Parameter{Real}}
 @test isequal(term2, b)