/**
* Evaluate the specified command.
*
* @param command The command.
* @return The return value of the command, or null if there is none.
* @exception Exception If something goes wrong processing the command.
*/
public String evaluateCommand(String command) throws Exception {
if (command.trim().equals("")) {
return "";
}
PtParser parser = new PtParser();
ASTPtRootNode node = parser.generateSimpleAssignmentParseTree(command);
String targetName = null;
// Figure out if we got an assignment... if so, then get the
// identifier name and only evaluated the expression part.
if (node instanceof ASTPtAssignmentNode) {
ASTPtAssignmentNode assignmentNode = (ASTPtAssignmentNode) node;
targetName = assignmentNode.getIdentifier();
node = assignmentNode.getExpressionTree();
}
final NamedObj model = ((ExpressionShellEffigy) getContainer()).getModel();
ParserScope scope =
new ModelScope() {
public ptolemy.data.Token get(String name) throws IllegalActionException {
Variable result = getScopedVariable(null, model, name);
if (result != null) {
return result.getToken();
} else {
return null;
}
}
public ptolemy.data.type.Type getType(String name) throws IllegalActionException {
Variable result = getScopedVariable(null, model, name);
if (result != null) {
return result.getType();
} else {
return null;
}
}
public InequalityTerm getTypeTerm(String name) throws IllegalActionException {
Variable result = getScopedVariable(null, model, name);
if (result != null) {
return result.getTypeTerm();
} else {
return null;
}
}
public Set identifierSet() {
return getAllScopedVariableNames(null, model);
}
};
Token result = _evaluator.evaluateParseTree(node, scope);
// If a target was specified, instantiate a new token.
if (targetName != null) {
Attribute attribute = model.getAttribute(targetName);
if (attribute != null && !(attribute instanceof Parameter)) {
attribute.setContainer(null);
attribute = null;
}
if (attribute == null) {
attribute = new Parameter(model, targetName);
}
((Parameter) attribute).setToken(result);
}
if (result == null) {
return "";
} else {
return result.toString();
}
}
