AstNode *
makeObject()
{
AstNode *object;
AstNode *equMeth,
*construct,
*destruct;
AstNode *declator,
*fparam;
AstNode *ret,
*eq;
Literal *classLit,
*oLit,
*equalsLit;
/*
* Build the
* int equals(Object o) { return this == o; }
* method.
*/
classLit = makeLiteral(OBJECT_NAME, 0);
oLit = makeLiteral("o", 0);
fparam = makeFormalParam(makeNameId(classLit), makeNameId(oLit), 0);
equalsLit = makeLiteral("equals", 0);
declator = makeMethDeclator(makeNameId(equalsLit), makeSeq(fparam), 0);
eq = makeBinaryOp(EQU_OP, makeThis(0), makeExprId(oLit), 0);
ret = makeReturnSt(eq, 0);
equMeth = makeMethDecl(makeInt(0), declator, makeSeq(ret), 0);
/*
* Build
* Object() { return; }
* constructor
*/
declator = makeConstDeclator(makeNameId(classLit), NULL, 0);
construct = makeConstDecl(declator, makeSeq(makeReturnSt(NULL, 0)), 0);
/*
* Build
* ~Object() { return; }
* destructor
*/
destruct = makeDestructor(makeNameId(classLit),
makeSeq(makeReturnSt(NULL, 0)), 0);
/*
* Link the class all together.
*/
object = makeClass(makeNameId(classLit), NULL,
appendSeq(appendSeq(makeSeq(equMeth),
makeSeq(construct)),
makeSeq(destruct)), 0);
return object;
}
WString& WString::operator+= (const char *rhs)
{
makeLiteral();
utf8_ += Wt::toUTF8(rhs);
return *this;
}
WString& WString::operator+= (const WString& rhs)
{
makeLiteral();
utf8_ += rhs.toUTF8();
return *this;
}
AstNode *
makeDefaultDestructor(ClassType * class_type)
{
AstNode *dest;
dest = makeDestructor(makeNameId(makeLiteral(class_type->name, 0)),
makeSeq(makeReturnSt(NULL, 0)), 0);
return makeSeq(dest);
}
AstNode *
makeDefaultConstructor(MethodType * cons)
{
NameId *nameid;
MethDeclator *mdeclator;
ConstInvoc *cinvoc;
MemberDecl *mdecl;
Literal *lit;
lit = makeLiteral(cons->name, 0);
nameid = (NameId *) makeNameId(lit);
mdeclator = (MethDeclator *) makeConstDeclator(&nameid->super, NULL, 0);
cinvoc = (ConstInvoc *) makeConstInvoc(makeSuper(0), NULL, 0);
mdecl = (MemberDecl *) makeConstDecl(&mdeclator->super,
makeSeq(&cinvoc->super.super), 0);
mdecl->t = &cons->super;
return makeSeq(&mdecl->super);
}
/** Parse with one token worth of look-ahead, return the expression object representing
the syntax parsed.
@param tok next token from the input.
@param fp file subsequent tokens are being read from.
@return the expression object constructed from the input.
*/
Expr *parse( char *tok, FILE *fp )
{
// Create a literal token for anything that looks like a number.
{
long dummy;
int pos;
// See if the whole token parses as a long int.
if ( sscanf( tok, "%ld%n", &dummy, &pos ) == 1 &&
pos == strlen( tok ) ) {
// Copy the literal to a dynamically allocated string, since makeLiteral wants
// a string it can keep.
char *str = (char *) malloc( strlen( tok ) + 1 );
return makeLiteral( strcpy( str, tok ) );
}
}
// Create a literal token for a quoted string, without the quotes.
if ( tok[ 0 ] == '"' ) {
// Same as above, make a dynamically allocated copy of the token that the literal
// expression can keep as long as at wants to.
int len = strlen( tok );
char *str = (char *) malloc( len - 1 );
strncpy( str, tok + 1, len - 2 );
str[ len - 2 ] = '\0';
return makeLiteral( str );
}
// Handle compound statements
if ( strcmp( tok, "{" ) == 0 ) {
int len = 0;
int cap = INITIAL_CAPACITY;
Expr **eList = (Expr **) malloc( cap * sizeof( Expr * ) );
// Keep parsing subexpressions until we hit the closing curly bracket.
while ( strcmp( expectToken( tok, fp ), "}" ) != 0 ) {
if ( len >= cap )
eList = (Expr **) realloc( eList, ( cap *= 2 ) * sizeof( Expr * ) );
eList[ len++ ] = parse( tok, fp );
}
return makeCompound( eList, len );
}
// Handle language operators (reserved words)
if ( strcmp( tok, "print" ) == 0 ) {
// Parse the one argument to print, and create a print expression.
Expr *arg = parse( expectToken( tok, fp ), fp );
return makePrint( arg );
}
if ( strcmp( tok, "set" ) == 0 ) {
// Parse the two operands, then make a set expression with them.
char *str = expectToken( tok, fp );
int len = strlen( str );
char *name = (char *) malloc( len + 1 );
strcpy( name, str );
name[ len ] = '\0';
if ( !isalpha(name[0]) || strlen( name ) > MAX_VAR || strchr( name, LEFT_BRACKET ) || strchr( name, RIGHT_BRACKET ) || strchr( name, POUND ) ) {
// Complain if we can't make sense of the variable.
fprintf( stderr, "line %d: invalid variable name \"%s\"\n", linesRead(), name );
exit( EXIT_FAILURE );
}
Expr *expr = parse( expectToken( tok, fp ), fp );
Expr *set = makeSet
( name, expr );
free(name);
return set;
}
if ( strcmp( tok, "add" ) == 0 ) {
// Parse the two operands, then make an add expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeAdd( op1, op2 );
}
if ( strcmp( tok, "sub" ) == 0 ) {
// Parse the two operands, then make a sub expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeSub( op1, op2 );
}
if ( strcmp( tok, "mul" ) == 0 ) {
// Parse the two operands, then make a mul expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeMul( op1, op2 );
}
if ( strcmp( tok, "div" ) == 0 ) {
// Parse the two operands, then make a div expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeDiv
( op1, op2 );
}
if ( strcmp( tok, "equal" ) == 0 ) {
// Parse the two operands, then make an equal expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeEqual
( op1, op2 );
}
if ( strcmp( tok, "less" ) == 0 ) {
// Parse the two operands, then make a less expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeLess
( op1, op2 );
}
if ( strcmp( tok, "not" ) == 0 ) {
// Parse the operand, then make a not expression with it.
Expr *op = parse( expectToken( tok, fp ), fp );
return makeNot
( op );
}
if ( strcmp( tok, "and" ) == 0 ) {
// Parse the two operands, then make an and expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeAnd
( op1, op2 );
}
if ( strcmp( tok, "or" ) == 0 ) {
// Parse the two operands, then make an or expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeOr
( op1, op2 );
}
if ( strcmp( tok, "if" ) == 0 ) {
// Parse the two operands, then make an if expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeIf
( op1, op2 );
}
if ( strcmp( tok, "while" ) == 0 ) {
// Parse the two operands, then make a while expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeWhile
( op1, op2 );
}
if ( strcmp( tok, "concat" ) == 0 ) {
// Parse the two operands, then make a concatenation expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
return makeConcat
( op1, op2 );
}
if ( strcmp( tok, "substr" ) == 0 ) {
// Parse the three operands, then make a substring expression with them.
Expr *op1 = parse( expectToken( tok, fp ), fp );
Expr *op2 = parse( expectToken( tok, fp ), fp );
Expr *op3 = parse( expectToken( tok, fp ), fp );
return makeSubstr
( op1, op2, op3 );
}
// Handle variables
if ( isalpha(tok[0]) && strlen( tok ) <= MAX_VAR && !strchr( tok, LEFT_BRACKET ) && !strchr( tok, RIGHT_BRACKET ) && !strchr( tok, POUND ) ) {
// Parse the variable name and make a variable expression.
char *str = tok;
int len = strlen( str );
char *name = (char *) malloc( len + 1 );
strcpy( name, str );
name[ len ] = '\0';
Expr *var = makeVariable( name );
free(name);
return var;
}
// Complain if we can't make sense of the token.
fprintf( stderr, "line %d: invalid token \"%s\"\n", linesRead(), tok );
exit( EXIT_FAILURE );
// Never reached.
return NULL;
}
