patrick
/
anthem
1
0
Fork 0
Code Issues 15 Releases 21 Activity

Minor refactoring.

This commit is contained in:
Patrick Lühne 2017-06-04 14:47:53 +02:00
parent dcc504ebc0
commit ab71e8eb0a
No known key found for this signature in database
GPG Key ID: 05F3611E97A70ABF
1 changed files with 11 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/anthem/Simplification.cpp
View File

@ -15,19 +15,19 @@ namespace anthem
////////////////////////////////////////////////////////////////////////////////////////////////////
// Determines whether a term is a specific variable
bool matchesVariableDeclaration(const ast::Term &term, const ast::VariableDeclaration *variableDeclaration)
bool matchesVariableDeclaration(const ast::Term &term, const ast::VariableDeclaration &variableDeclaration)
{
if (!term.is<ast::Variable>())
return false;
return term.get<ast::Variable>().declaration == variableDeclaration;
return term.get<ast::Variable>().declaration == &variableDeclaration;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
// Extracts the term t if the given formula is of the form “X = t” and X matches the given variable
// The input formula is not usable if a term is returned
std::experimental::optional<ast::Term> extractAssignedTerm(ast::Formula &formula, const ast::VariableDeclaration *variableDeclaration)
std::experimental::optional<ast::Term> extractAssignedTerm(ast::Formula &formula, const ast::VariableDeclaration &variableDeclaration)
{
if (!formula.is<ast::Comparison>())
return std::experimental::nullopt;
@ -51,16 +51,16 @@ std::experimental::optional<ast::Term> extractAssignedTerm(ast::Formula &formula
// Replaces all occurrences of a variable in a given term with another term
struct ReplaceVariableInTermVisitor : public ast::RecursiveTermVisitor<ReplaceVariableInTermVisitor>
{
static void accept(ast::Variable &variable, ast::Term &term, const ast::VariableDeclaration *original, const ast::Term &replacement)
static void accept(ast::Variable &variable, ast::Term &term, const ast::VariableDeclaration &original, const ast::Term &replacement)
{
if (variable.declaration == original)
if (variable.declaration == &original)
// No dangling variables can result from this operation, and hence, fixing them is not necessary
term = ast::prepareCopy(replacement);
}
// Ignore all other types of expressions
template<class T>
static void accept(T &, ast::Term &, const ast::VariableDeclaration *, const ast::Term &)
static void accept(T &, ast::Term &, const ast::VariableDeclaration &, const ast::Term &)
{
}
};
@ -70,19 +70,19 @@ struct ReplaceVariableInTermVisitor : public ast::RecursiveTermVisitor<ReplaceVa
// Replaces all occurrences of a variable in a given formula with a term
struct ReplaceVariableInFormulaVisitor : public ast::RecursiveFormulaVisitor<ReplaceVariableInFormulaVisitor>
{
static void accept(ast::Comparison &comparison, ast::Formula &, const ast::VariableDeclaration *original, const ast::Term &replacement)
static void accept(ast::Comparison &comparison, ast::Formula &, const ast::VariableDeclaration &original, const ast::Term &replacement)
{
comparison.left.accept(ReplaceVariableInTermVisitor(), comparison.left, original, replacement);
comparison.right.accept(ReplaceVariableInTermVisitor(), comparison.right, original, replacement);
}
static void accept(ast::In &in, ast::Formula &, const ast::VariableDeclaration *original, const ast::Term &term)
static void accept(ast::In &in, ast::Formula &, const ast::VariableDeclaration &original, const ast::Term &term)
{
in.element.accept(ReplaceVariableInTermVisitor(), in.element, original, term);
in.set.accept(ReplaceVariableInTermVisitor(), in.set, original, term);
}
static void accept(ast::Predicate &predicate, ast::Formula &, const ast::VariableDeclaration *original, const ast::Term &replacement)
static void accept(ast::Predicate &predicate, ast::Formula &, const ast::VariableDeclaration &original, const ast::Term &replacement)
{
for (auto &argument : predicate.arguments)
argument.accept(ReplaceVariableInTermVisitor(), argument, original, replacement);
@ -90,7 +90,7 @@ struct ReplaceVariableInFormulaVisitor : public ast::RecursiveFormulaVisitor<Rep
// Ignore all other types of expressions
template<class T>
static void accept(T &, ast::Formula &, const ast::VariableDeclaration *, const ast::Term &)
static void accept(T &, ast::Formula &, const ast::VariableDeclaration &, const ast::Term &)
{
}
};
@ -110,7 +110,7 @@ void simplify(ast::Exists &exists, ast::Formula &formula)
// Simplify formulas of type “exists X (X = t and F(X))” to “F(t)”
for (auto i = exists.variables.begin(); i != exists.variables.end();)
{
const auto *variableDeclaration = i->get();
const auto &variableDeclaration = **i;
bool wasVariableReplaced = false;