ValueBindingPtr Parser::parseVariableDeclaration()
{
Token token;
Attributes attrs;
PatternPtr key = parsePattern();
TypeNodePtr type = NULL;
ExpressionPtr val = NULL;
if(match(L":"))
{
type = parseTypeAnnotation();
}
if(match(L"="))
{
Flags flags(this, SUPPRESS_TRAILING_CLOSURE);
val = parseExpression();
}
ValueBindingPtr ret = nodeFactory->createValueBinding(*key->getSourceInfo());
if(TypedPatternPtr p = std::dynamic_pointer_cast<TypedPattern>(key))
{
ret->setName(p->getPattern());
ret->setDeclaredType(p->getDeclaredType());
}
else
{
ret->setName(key);
ret->setDeclaredType(type);
}
ret->setTypeAttributes(attrs);
ret->setInitializer(val);
return ret;
}
/*
GRAMMAR OF A CONSTANT DECLARATION
constant-declaration → attributes opt declaration-specifiers opt let pattern-initializer-list
pattern-initializer-list → pattern-initializer | pattern-initializer,pattern-initializer-list
pattern-initializer → pattern initializer opt
initializer → =expression
*/
DeclarationPtr Parser::parseLet(const std::vector<AttributePtr>& attrs, int specifiers)
{
Token token;
Flags flag(this, UNDER_LET);
expect(Keyword::Let, token);
ValueBindingsPtr ret = nodeFactory->createValueBindings(token.state);
ret->setReadOnly(true);
ret->setAttributes(attrs);
ret->setSpecifiers(specifiers);
do
{
PatternPtr pattern = parsePattern();
ExpressionPtr initializer = NULL;
if(match(L"="))
{
initializer = parseExpression();
}
ValueBindingPtr constant = nodeFactory->createValueBinding(*pattern->getSourceInfo());
constant->setAttributes(attrs);
constant->setSpecifiers(specifiers);
constant->setName(pattern);
TypedPatternPtr typedPattern = std::dynamic_pointer_cast<TypedPattern>(pattern);
if(typedPattern)
{
//promote typed pattern
constant->setDeclaredType(typedPattern->getDeclaredType());
constant->setName(typedPattern->getPattern());
}
constant->setInitializer(initializer);
ret->add(constant);
}while(match(L","));
return ret;
}