/// <summary>
/// Evaluates a single function call particle, and returns the result as a value (NOT using particle manager).
/// </summary>
public override object VisitFunctionCall_particle([NotNull] algoParser.FunctionCall_particleContext context)
{
//Set up an old scope.
AlgoScopeCollection oldScope = null;
//Get the previous particle output.
var current = Particles.GetParticleResult();
//Right length of parameters?
var paramCtx = context.literal_params();
int givenNumParams = 0;
if (paramCtx != null)
{
givenNumParams = paramCtx.expr().Length;
}
else if (current.Type == AlgoValueType.EmulatedFunction)
{
var func = ((AlgoPluginFunction)current.Value);
int paramNum = func.ParameterCount;
if (givenNumParams != paramNum)
{
Error.Fatal(context, "Invalid number of parameters for function '" + func.Name + "' (Expected " + func.ParameterCount + ", got " + givenNumParams + ").");
return(null);
}
}
else if (current.Type == AlgoValueType.Function)
{
var func = ((AlgoFunction)current.Value);
int paramNum = func.Parameters.Count;
if (givenNumParams != paramNum)
{
Error.Fatal(context, "Invalid number of parameters for function '" + func.Name + "' (Expected " + func.Parameters.Count + ", got " + givenNumParams + ").");
return(null);
}
}
//Evaluate all the parameters, in the paramScope if necessary.
if (Particles.funcArgumentScopes != null)
{
oldScope = Scopes;
Scopes = Particles.funcArgumentScopes;
}
List <AlgoValue> params_ = new List <AlgoValue>();
if (paramCtx != null)
{
foreach (var paramToEval in paramCtx.expr())
{
params_.Add((AlgoValue)VisitExpr(paramToEval));
}
}
//Switch back scopes.
if (Particles.funcArgumentScopes != null)
{
Scopes = oldScope;
}
//Depending on the type of function, execute.
if (current.Type == AlgoValueType.Function)
{
//STANDARD FUNCTION
var func = (AlgoFunction)current.Value;
//Create a new scope, add the parameters to it.
Scopes.AddScope();
for (int i = 0; i < params_.Count; i++)
{
Scopes.AddVariable(func.Parameters[i], params_[i], context);
}
//Running the function's body.
foreach (var statement in func.Body)
{
AlgoValue returned = (AlgoValue)VisitStatement(statement);
if (returned != null)
{
//Normal function, remove scope and return.
Scopes.RemoveScope();
return(returned);
}
}
//Remove the scope.
Scopes.RemoveScope();
//Return nothing, no result.
return(null);
}
else if (current.Type == AlgoValueType.EmulatedFunction)
{
//EMULATED FUNCTION
var func = (AlgoPluginFunction)current.Value;
//Attempt to evaluate, and return result.
AlgoValue returned = null;
try
{
returned = func.Function(context, params_.ToArray());
}
catch (Exception e)
{
Error.Fatal(context, "External function returned an error, " + e.Message);
return(null);
}
return(returned);
}
else
{
//Unsupported uncaught function type.
Error.Internal("Unsupported uncaught function type detected (" + current.Type.ToString() + "), cannot execute.");
return(null);
}
}
//An "if" statement.
public override object VisitStat_if([NotNull] algoParser.Stat_ifContext context)
{
//Evaluate the check.
AlgoValue checkReturned = (AlgoValue)VisitCheck(context.check());
bool mainCheck = AlgoComparators.GetBooleanValue(checkReturned, context);
//Did it pass? If so, eval the if.
if (mainCheck)
{
//Create scope.
Scopes.AddScope();
//Evaluate the main statement body.
foreach (var statement in context.statement())
{
AlgoValue returned = (AlgoValue)VisitStatement(statement);
if (returned != null)
{
Scopes.RemoveScope();
return(returned);
}
}
//Delete scope.
Scopes.RemoveScope();
//Return.
return(null);
}
//Maincheck failed, complete all the "else if" checks if they exist.
if (context.stat_elif().Length != 0)
{
foreach (var elseifblock in context.stat_elif())
{
//Does the check pass?
var checkContext = elseifblock.check();
AlgoValue elifCheckReturned = (AlgoValue)VisitCheck(checkContext);
bool elseifCheck = AlgoComparators.GetBooleanValue(elifCheckReturned, context);
if (elseifCheck)
{
//Create scope.
Scopes.AddScope();
//Evaluate statements.
foreach (var statement in elseifblock.statement())
{
AlgoValue returned = (AlgoValue)VisitStatement(statement);
if (returned != null)
{
Scopes.RemoveScope();
return(returned);
}
}
//Remove scope.
Scopes.RemoveScope();
//Return.
return(null);
}
}
}
//Is there an else?
if (context.stat_else() != null)
{
//Create a scope.
Scopes.AddScope();
//Evaluate statements.
foreach (var statement in context.stat_else().statement())
{
AlgoValue returned = (AlgoValue)VisitStatement(statement);
if (returned != null)
{
Scopes.RemoveScope();
return(returned);
}
}
//Deleting scope.
Scopes.RemoveScope();
}
//Returning.
return(null);
}
//When a try/catch block is executed.
public override object VisitStat_try_catch([NotNull] algoParser.Stat_try_catchContext context)
{
//Turn on execution catch mode.
AlgoRuntimeInformation.CatchExceptions = true;
//Loop over the statements, execute all.
bool foundError = false;
string errorMessage = "";
Scopes.AddScope();
foreach (var statement in context.block()[0].statement())
{
//Execute statement.
AlgoValue returned = null;
try
{
returned = (AlgoValue)VisitStatement(statement);
}
catch (Exception e)
{
//C# error somewhere up the heirarchy, 90% means an error has been thrown.
foundError = true;
errorMessage = "Internal Language Error: " + e.Message;
}
//Check if an error has been found.
if (AlgoRuntimeInformation.ExceptionCaught())
{
//Yep, break out to the catch block.
foundError = true;
errorMessage = AlgoRuntimeInformation.GetExceptionMessage();
AlgoRuntimeInformation.CatchExceptions = false;
break;
}
//If something was actually returned, return it up.
if (returned != null)
{
AlgoRuntimeInformation.CatchExceptions = false;
Scopes.RemoveScope();
return(returned);
}
}
Scopes.RemoveScope();
//Turn off error catching.
AlgoRuntimeInformation.CatchExceptions = false;
//Done executing try statements, did an error come back?
if (!foundError)
{
return(null);
}
//Yep, get the identifier to use for the error message, check it doesn't exist.
if (Scopes.VariableExists(context.IDENTIFIER().GetText()))
{
Error.Fatal(context, "A variable already exists named '" + context.IDENTIFIER().GetText() + "', cannot use for catch parameter.");
return(null);
}
//Create it, assign it the caught value.
Scopes.AddScope();
Scopes.AddVariable(context.IDENTIFIER().GetText(), new AlgoValue()
{
Type = AlgoValueType.String,
Value = errorMessage
}, context);
//Execute what's in the catch scope.
foreach (var statement in context.block()[1].statement())
{
AlgoValue returned = (AlgoValue)VisitStatement(statement);
if (returned != null)
{
Scopes.RemoveScope();
return(returned);
}
}
//Finished!
return(null);
}