TVariablePtr ExpressionParser::Parse(StringPtrLen str)
{
CheckBracketBalance(str);
TVariablePtr variable;
auto assignment = FindWithZeroBalance(str, g_token_assignment);
if (assignment != nullptr)
{
variable = ParseVariableDeclaration(str.Left(assignment));
str = str.Right(assignment + std::strlen(g_token_assignment));
}
else
{
// Unnamed variable
variable = std::make_unique<Variable>();
}
m_curr_variable = variable.get();
auto expression = ParseExpression(str);
m_curr_variable = nullptr;
NormalizeExpression(expression);
SimplifyExpression(expression);
variable->SetExpression(std::move(expression));
return variable;
}
// ParseUnnamedVariableConcatenation
//------------------------------------------------------------------------------
bool BFFParser::ParseUnnamedVariableConcatenation( BFFIterator & iter )
{
ASSERT( *iter == BFF_VARIABLE_CONCATENATION );
// have we assigned a variable before?
if ( m_SeenAVariable == false )
{
Error::Error_1011_UnnamedConcatMustFollowAssignment( iter );
return false;
}
return ParseVariableDeclaration( iter, m_LastVarNameStart, m_LastVarNameEnd );
}
// ParseUnnamedVariableModification
//------------------------------------------------------------------------------
bool BFFParser::ParseUnnamedVariableModification( BFFIterator & iter )
{
ASSERT( ( *iter == BFF_VARIABLE_CONCATENATION ) ||
( *iter == BFF_VARIABLE_SUBTRACTION ) );
// have we assigned a variable before?
if ( m_SeenAVariable == false )
{
Error::Error_1011_UnnamedModifcationMustFollowAssignment( iter );
return false;
}
return ParseVariableDeclaration( iter, m_LastVarName, m_LastVarFrame );
}
ListaVariables* Sintactico::ParseVariableDeclarationList()
{
DeclaracionVariable* decl_var = ParseVariableDeclaration();
ListaVariables* lista_var = _ParseVariableDeclarationList();
list<string> ids = decl_var->GetIds();
list<string>::iterator it;
for ( it = ids.begin() ; it != ids.end() ; it++)
{
lista_var->insert((*it),decl_var->GetTipo() );
}
return lista_var;
}
// ParseNamedVariableDeclaration
//------------------------------------------------------------------------------
bool BFFParser::ParseNamedVariableDeclaration( BFFIterator & iter )
{
// skip over the declaration symbol
ASSERT( *iter == BFF_DECLARE_VAR_INTERNAL );
m_LastVarNameStart = iter; // include type token in var name
iter++;
// make sure we haven't hit the end of the file
if ( iter.IsAtEnd() )
{
Error::Error_1012_UnexpectedEndOfFile( iter );
return false;
}
// make sure immediately after the symbol starts a variable name
if ( iter.IsAtValidVariableNameCharacter() == false )
{
Error::Error_1013_UnexpectedCharInVariableName( iter, nullptr );
return false;
}
// find the end of the variable name
iter.SkipVariableName();
if ( iter.IsAtEnd() )
{
Error::Error_1012_UnexpectedEndOfFile( iter );
return false;
}
m_LastVarNameEnd = iter;
// sanity check it is a sensible length
size_t varNameLen = m_LastVarNameStart.GetDistTo( m_LastVarNameEnd );
if ( varNameLen > MAX_VARIABLE_NAME_LENGTH )
{
Error::Error_1014_VariableNameIsTooLong( iter, (uint32_t)varNameLen, (uint32_t)MAX_VARIABLE_NAME_LENGTH );
return false;
}
// find the start of the assignment
iter.SkipWhiteSpaceAndComments();
if ( iter.IsAtEnd() )
{
Error::Error_1012_UnexpectedEndOfFile( iter );
return false;
}
return ParseVariableDeclaration( iter, m_LastVarNameStart, m_LastVarNameEnd );
}
// ParseNamedVariableDeclaration
//------------------------------------------------------------------------------
bool BFFParser::ParseNamedVariableDeclaration( BFFIterator & iter )
{
const BFFIterator varNameStart( iter );
bool parentScope = false;
if ( ParseVariableName( iter, m_LastVarName, parentScope ) == false )
{
return false; // ParseVariableName() would have display an error
}
// find the start of the assignment
iter.SkipWhiteSpaceAndComments();
if ( iter.IsAtEnd() )
{
Error::Error_1012_UnexpectedEndOfFile( iter );
return false;
}
// check if points to a previous declaration in a parent scope
const BFFVariable * parentVar = nullptr;
m_LastVarFrame = ( parentScope )
? BFFStackFrame::GetParentDeclaration( m_LastVarName, nullptr, parentVar )
: nullptr;
if ( parentScope )
{
// check if a parent definition exists
if ( nullptr == m_LastVarFrame )
{
Error::Error_1009_UnknownVariable( varNameStart, nullptr );
return false;
}
ASSERT( nullptr != parentVar );
// check if the parent definition is frozen
if ( parentVar->Frozen() )
{
Error::Error_1060_CantModifyFrozenVar( varNameStart, nullptr, parentVar );
return false;
}
}
return ParseVariableDeclaration( iter, m_LastVarName, m_LastVarFrame );
}
ListaVariables* Sintactico::_ParseVariableDeclarationList()
{
ListaVariables* lista_var = new ListaVariables();
//Utilizamos Primero( VariableDeclarationList )
if ( proximo_token.GetTipo() == id )
{
DeclaracionVariable* decl_var = ParseVariableDeclaration();
lista_var = _ParseVariableDeclarationList();
list<string> ids = decl_var->GetIds();
list<string>::iterator it;
for ( it = ids.begin() ; it != ids.end() ; it++)
{
lista_var->insert((*it),decl_var->GetTipo() );
}
}
return lista_var;
}
