//Checks whether a variable exists.
public bool VariableExists(string varname)
{
if (varname.Contains('.'))
{
//Validate it by fake value grabbing.
List <string> parts = varname.Split('.').ToList();
AlgoValue partParent = GetVariable(parts[0]);
if (partParent == null || (partParent.Type != AlgoValueType.Object && parts.Count > 1))
{
return(false);
}
//If the variable is known to exist and no points, this is just a sanity check to make sure nothing slips through.
if (parts.Count == 1)
{
return(true);
}
//Iterate through children recursively to check they all exist.
AlgoObject currentObj = (AlgoObject)partParent.Value;
parts.RemoveAt(0);
string childString = string.Join(".", parts.ToArray());
//Recursive return.
return(currentObj.ObjectScopes.VariableExists(childString));
}
return(GetVariable(varname) != null);
}
//Returns the value of a referenced object within an object string.
private AlgoValue GetValueFromObjectString(string objString)
{
//Splitting the string by "." to get individual variable parts.
string[] objParts = objString.Split('.');
if (objParts.Length == 1)
{
if (!VariableExists(objString))
{
return(null);
}
return(GetVariable(objString));
}
//Loop and get value.
if (!VariableExists(objParts[0]))
{
return(null);
}
//Get the first parent object.
AlgoValue currentObjValue = GetVariable(objParts[0]);
if (currentObjValue.Type != AlgoValueType.Object)
{
return(null);
}
//Getting the deepest scope.
AlgoObject currentObj = (AlgoObject)currentObjValue.Value;
for (int i = 1; i < objParts.Length - 1; i++)
{
//Attempt to get the child.
if (!currentObj.ObjectScopes.VariableExists(objParts[i]))
{
return(null);
}
currentObjValue = currentObj.ObjectScopes.GetVariable(objParts[i]);
//Check if it's an object.
if (currentObjValue.Type != AlgoValueType.Object)
{
return(null);
}
//Set current object.
currentObj = (AlgoObject)currentObjValue.Value;
}
//Getting the variable referenced at the deepest scope.
if (!currentObj.ObjectScopes.VariableExists(objParts[objParts.Length - 1]))
{
return(null);
}
//Returning it.
return(currentObj.ObjectScopes.GetVariable(objParts[objParts.Length - 1]));
}
//Add a variable to the scope.
public void AddVariable(string name, AlgoValue value, ParserRuleContext context = null)
{
//Is it an object member?
if (!name.Contains("."))
{
//Check if a variable with this name already exists.
if (VariableExistsLowest(name))
{
Error.Fatal(context, "A variable with this name already exists, cannot create one.");
return;
}
//Nope, add it to the lowest scope.
Scopes[Scopes.Count - 1].Add(name, value);
}
else
{
//Object member, a more complicated procedure.
//Get the parent object that the member is being assigned to.
string objTxt = name;
List <string> objParts = objTxt.Split('.').ToList();
string final = objParts.Last();
objParts.RemoveAt(objParts.Count - 1);
objTxt = string.Join(".", objParts.ToArray());
if (!VariableExists(objTxt))
{
Error.Fatal(context, "Cannot create an object member for nonexistant object '" + objTxt + "'.");
}
//Check if the variable is an object.
AlgoValue objVal = GetVariable(objTxt);
if (objVal.Type != AlgoValueType.Object)
{
Error.Fatal(context, "Cannot create an object member of non-object value '" + objTxt + "'.");
}
AlgoObject obj = (AlgoObject)objVal.Value;
//Check if the variable has the new member already defined.
if (obj.ObjectScopes.VariableExists(final))
{
Error.Fatal(context, "An object member with that name already exists.");
}
//Create the variable.
obj.ObjectScopes.AddVariable(final, value);
//Set the object parent.
SetVariable(objTxt, new AlgoValue()
{
Type = AlgoValueType.Object,
Value = obj
});
}
}
//When an enum is first defined.
public override object VisitStat_enumDef([NotNull] algoParser.Stat_enumDefContext context)
{
//Check if the variable already exists at local scope.
if (Scopes.VariableExistsLowest(context.IDENTIFIER().GetText()))
{
Error.Fatal(context, "A variable with the name '" + context.IDENTIFIER().GetText() + "'already exists, cannot create a duplicate.");
return(null);
}
//Create an object for the enum.
AlgoObject enumObj = new AlgoObject();
//For each enum member, create a child in the object with an integer value.
BigInteger enumIndex = 0;
if (context.abstract_params() != null)
{
foreach (var id in context.abstract_params().IDENTIFIER())
{
//Does a member with this name already exist?
if (enumObj.ObjectScopes.VariableExists(id.GetText()))
{
Error.Fatal(context, "An enum member with the name '" + id.GetText() + "' already exists.");
return(null);
}
//Add member.
enumObj.ObjectScopes.AddVariable(id.GetText(), new AlgoValue()
{
Type = AlgoValueType.Integer,
Value = enumIndex
});
enumIndex++;
}
}
//Create an enum variable with this name.
Scopes.AddVariable(context.IDENTIFIER().GetText(), new AlgoValue()
{
Type = AlgoValueType.Object,
Value = enumObj
});
return(null);
}
//Remove a variable from the scope.
public void RemoveVariable(string name)
{
//Check if a variable with this name exists.
if (!VariableExists(name))
{
Error.FatalNoContext("No variable with this name exists, so can't destroy it.");
return;
}
//If the name contains a '.', got to go to deepest scope recursively.
if (name.Contains('.'))
{
//Get the parent.
List <string> parts = name.Split('.').ToList();
AlgoValue partParent = GetVariable(parts[0]);
//Checking if it's an object.
if (partParent.Type != AlgoValueType.Object)
{
Error.FatalNoContext("The value given is not an object, so cannot remove children.");
return;
}
//Remove variable from this scope recursively.
parts.RemoveAt(0);
string newPartString = string.Join(".", parts.ToList());
AlgoObject partObj = (AlgoObject)partParent.Value;
partObj.ObjectScopes.RemoveVariable(newPartString);
}
else
{
//Literal variable in this scope, check through all scopes (from deepest) and delete.
for (int i = Scopes.Count - 1; i >= 0; i--)
{
if (Scopes[i].ContainsKey(name))
{
Scopes[i].Remove(name);
return;
}
}
}
//Could not find.
Error.FatalNoContext("Could not find variable to delete, despite the fact it exists.");
}
//When a single value is visited in Algo.
public override object VisitValue([NotNull] algoParser.ValueContext context)
{
//Check what type the value is.
if (context.INTEGER() != null)
{
//INTEGER
return(new AlgoValue()
{
Type = AlgoValueType.Integer,
Value = BigInteger.Parse(context.INTEGER().GetText()),
});
}
else if (context.FLOAT() != null)
{
//FLOAT
return(new AlgoValue()
{
Type = AlgoValueType.Float,
Value = BigFloat.Parse(context.FLOAT().GetText()),
});
}
else if (context.STRING() != null)
{
//STRING
return(new AlgoValue()
{
Type = AlgoValueType.String,
Value = context.STRING().GetText().Substring(1, context.STRING().GetText().Length - 2)
//text escape codes
.Replace("\\n", "\n")
.Replace("\\t", "\t")
.Replace("\\r", "\r")
.Replace("\\q", "\"")
});
}
else if (context.RATIONAL() != null)
{
//RATIONAL
//Get the two integer halves from the rational.
string[] halves = context.RATIONAL().GetText().Split('/');
string numerator = halves[0];
string denominator = halves[1];
return(new AlgoValue()
{
Type = AlgoValueType.Rational,
Value = new BigRational(BigInteger.Zero, new Fraction(BigInteger.Parse(numerator), BigInteger.Parse(denominator))),
});
}
else if (context.BOOLEAN() != null)
{
//BOOLEAN
return(new AlgoValue()
{
Type = AlgoValueType.Boolean,
Value = (context.BOOLEAN().GetText() == "true"),
});
}
else if (context.HEX() != null)
{
//BYTES
return(new AlgoValue()
{
Type = AlgoValueType.Bytes,
Value = context.HEX().GetText().ToByteArray()
});
}
else if (context.NULL() != null)
{
//NULL VALUE
return(new AlgoValue()
{
Type = AlgoValueType.Null,
Value = null,
});
}
else if (context.IDENTIFIER() != null)
{
//VARIABLE/OBJECT
return(Particles.ParseParticleBlock(this, context, context.IDENTIFIER(), context.particle()));
}
else if (context.stat_functionCall() != null)
{
//FUNCTION CALL
AlgoValue value = (AlgoValue)VisitStat_functionCall(context.stat_functionCall());
if (value != null)
{
return(value);
}
else
{
//Return a null value.
return(new AlgoValue()
{
Type = AlgoValueType.Null,
Value = null,
});
}
}
else if (context.array() != null)
{
//LIST.
//Evaluate all list items as expressions.
List <AlgoValue> list = new List <AlgoValue>();
foreach (var item in context.array().value())
{
list.Add((AlgoValue)VisitValue(item));
}
//Return as a single value.
return(new AlgoValue()
{
Type = AlgoValueType.List,
Value = list
});
}
else if (context.@object() != null)
{
//OBJECT DEFINITION
//Create a new object.
AlgoObject toReturn = new AlgoObject();
//Anything to enumerate?
if (context.@object().obj_child_definitions() == null)
{
//Nope.
return(new AlgoValue()
{
Type = AlgoValueType.Object,
Value = toReturn
});
}
//Enumerate through all the define statements and evaluate their values.
foreach (var value in context.@object().obj_child_definitions().obj_vardefine())
{
//Check if the variable already exists.
if (toReturn.ObjectScopes.VariableExists(value.IDENTIFIER().GetText()))
{
Error.Fatal(context, "The variable with name '" + value.IDENTIFIER().GetText() + "' is defined twice or more in an object.");
return(null);
}
//Evaluate the value on the right.
AlgoValue evaluated = (AlgoValue)VisitExpr(value.expr());
//Add the variable to scope.
toReturn.ObjectScopes.AddVariable(value.IDENTIFIER().GetText(), evaluated);
}
//Enumerate through all functions and define them.
foreach (var value in context.@object().obj_child_definitions().obj_funcdefine())
{
//Check if the variable already exists.
if (toReturn.ObjectScopes.VariableExists(value.IDENTIFIER().GetText()))
{
Error.Fatal(context, "The variable with name '" + value.IDENTIFIER().GetText() + "' is defined twice or more in an object.");
return(null);
}
//Create a list of parameters.
List <string> params_ = new List <string>();
if (value.abstract_params() != null)
{
foreach (var param in value.abstract_params().IDENTIFIER())
{
//Check if param already exists.
if (params_.Contains(param.GetText()))
{
Error.Fatal(context, "The parameter with name '" + param.GetText() + "' is already defined in the function.");
return(null);
}
params_.Add(param.GetText());
}
}
//Create a function, push.
AlgoFunction func = new AlgoFunction(value.statement().ToList(), params_, value.IDENTIFIER().GetText());
AlgoValue funcValue = new AlgoValue()
{
Type = AlgoValueType.Function,
Value = func,
};
toReturn.ObjectScopes.AddVariable(value.IDENTIFIER().GetText(), funcValue);
}
//Enumerate all external functions defined.
foreach (var ext in context.@object().obj_child_definitions().obj_externdefine())
{
//Get the value of the function.
var loadFuncStat = ext.stat_loadFuncExt();
AlgoValue func = Plugins.GetEmulatedFuncValue(loadFuncStat);
//Check if a variable with this name already exists.
if (toReturn.ObjectScopes.VariableExists(loadFuncStat.IDENTIFIER()[0].GetText()))
{
Error.Fatal(context, "A variable with the name '" + loadFuncStat.IDENTIFIER()[0].GetText() + "' already exists in this object. Cannot duplicate.");
return(null);
}
//Add that function to the return object.
toReturn.ObjectScopes.AddVariable(loadFuncStat.IDENTIFIER()[0].GetText(), func);
}
//Return the object.
return(new AlgoValue()
{
Type = AlgoValueType.Object,
Value = toReturn
});
}
else
{
//No proper detected value type.
Error.Fatal(context, "Unknown or invalid type given for value.");
return(new AlgoValue()
{
Type = AlgoValueType.Null,
Value = null
});
}
}
//Set a variable within the scopes.
//Start from deepest depth.
public void SetVariable(string varname, AlgoValue value, ParserRuleContext context = null)
{
//Is it a normal variable or an object?
if (!varname.Contains('.'))
{
//Finding and setting.
for (int i = Scopes.Count - 1; i >= 0; i--)
{
if (Scopes[i].Keys.Contains(varname))
{
Scopes[i][varname] = value;
return;
}
}
//Uncaught missing variable.
Error.Fatal(context, "No variable found with name '" + varname + "' to set.");
}
else
{
string[] objParts = varname.Split('.');
//Loop and get value.
if (!VariableExists(objParts[0]))
{
Error.Fatal(context, "No parent variable '" + objParts[0] + "' exists.");
}
AlgoValue currentObjValue = GetVariable(objParts[0]);
if (currentObjValue.Type != AlgoValueType.Object)
{
Error.Fatal(context, "Parent variable is not an object, so cannot access children.");
}
//Getting the deepest scope.
AlgoObject currentObj = (AlgoObject)currentObjValue.Value;
for (int i = 1; i < objParts.Length - 1; i++)
{
//Attempt to get the child.
if (!currentObj.ObjectScopes.VariableExists(objParts[i]))
{
Error.Fatal(context, "A child property '" + objParts[i] + "' does not exist.");
}
currentObjValue = currentObj.ObjectScopes.GetVariable(objParts[i]);
//Check if it's an object.
if (currentObjValue.Type != AlgoValueType.Object)
{
Error.Fatal(context, "A child property '" + objParts[i] + "' is not an object, so can't access further children.");
}
//Set current object.
currentObj = (AlgoObject)currentObjValue.Value;
}
//Getting the variable referenced at the deepest scope.
if (!currentObj.ObjectScopes.VariableExists(objParts[objParts.Length - 1]))
{
Error.Fatal(context, "No variable exists at the deepest scope with name '" + objParts[objParts.Length - 1] + "'.");
}
//Set value of variable.
currentObj.ObjectScopes.SetVariable(objParts[objParts.Length - 1], value);
}
}
/// <summary>
/// Evaluates a given particle, and returns the result.
/// </summary>
public override object VisitParticle([NotNull] algoParser.ParticleContext context)
{
//Get the last result of the particle before this.
AlgoValue current = Particles.GetParticleResult();
if (current == null)
{
Error.Internal("Particle chain started without setting an initial value.");
return(null);
}
//Prepare an "old" scope for swapping.
AlgoScopeCollection oldScope = null;
//What type of particle is it?
//CHILD VARIABLE
if (context.IDENTIFIER() != null)
{
//Sub-variable. Attempt to get from the object.
if (current.Type != AlgoValueType.Object)
{
Error.Fatal(context, "Cannot access children when given variable is not an object, and has no children to access.");
return(null);
}
//Does the sub-variable exist?
AlgoObject curObj = (AlgoObject)current.Value;
AlgoValue newObj = curObj.ObjectScopes.GetVariable(context.IDENTIFIER().GetText());
if (newObj == null)
{
Error.Fatal(context, "No child of the given object exists with name '" + context.IDENTIFIER().GetText() + "'.");
return(null);
}
//Yes, set result and return.
Particles.SetParticleInput(newObj);
return(null);
}
//ARRAY ACCESS
else if (context.array_access_particle() != null)
{
var aap = context.array_access_particle();
//Indexing.
//For each index, iterate over.
AlgoValue currentLV = current;
foreach (var index in aap.literal_params().expr())
{
//Is the current list value a list?
if (currentLV.Type != AlgoValueType.List)
{
Error.Fatal(context, "Cannot index into variable that is not a list or indexable object.");
return(null);
}
//Need to switch scopes for evaluating indexes?
if (Particles.funcArgumentScopes != null)
{
oldScope = Scopes;
Scopes = Particles.funcArgumentScopes;
}
//Evaluate the expression.
AlgoValue indexVal = (AlgoValue)VisitExpr(index);
//Back to normal.
if (Particles.funcArgumentScopes != null)
{
Scopes = oldScope;
}
//Valid?
if (indexVal.Type != AlgoValueType.Integer)
{
Error.Fatal(context, "Index value provided is not an integer. Indexes must be whole integer values.");
return(null);
}
//Is the index outside of the bounds of the array?
if (((List <AlgoValue>)currentLV.Value).Count <= (BigInteger)indexVal.Value)
{
Error.Fatal(context, "Index provided is outside the bounds of the array.");
return(null);
}
//Index into it, set the current value.
currentLV = ((List <AlgoValue>)currentLV.Value)[(int)((BigInteger)indexVal.Value)];
}
//Set result.
Particles.SetParticleInput(currentLV);
return(null);
}
//CHILD FUNCTION
else if (context.functionCall_particle() != null)
{
//Function call.
if (current.Type != AlgoValueType.Object)
{
Error.Fatal(context, "Cannot call a child function on a value with no children (given value was not an object).");
return(null);
}
//Get the child, see if it's a function.
AlgoObject thisObj = current.Value as AlgoObject;
string funcName = context.functionCall_particle().IDENTIFIER().GetText();
AlgoValue childFunc = thisObj.ObjectScopes.GetVariable(funcName);
if (childFunc == null || (childFunc.Type != AlgoValueType.Function && childFunc.Type != AlgoValueType.EmulatedFunction))
{
Error.Fatal(context, "No child function exists with name '" + funcName + "'.");
return(null);
}
//Set the particle result as the function value, call the function call particle.
Particles.SetParticleInput(childFunc);
var result = VisitFunctionCall_particle(context.functionCall_particle());
if (result == null)
{
Particles.ResetParticleInput(); //Returned no result.
}
else
{
//A result came back, set input for the next particle.
Particles.SetParticleInput((AlgoValue)result);
}
return(null);
}
else
{
//Unrecognized!
Error.Internal("Unrecognized particle type to parse, implementation either unfinished or incorrect.");
return(null);
}
}
//When a function is called.
public override object VisitStat_functionCall([NotNull] algoParser.Stat_functionCallContext context)
{
//If there are particles, get the last value.
AlgoValue currentVal = null; bool isLibraryTopLevelCall = false;
if (context.IDENTIFIER() != null)
{
//Is the identifier a library and has no particles?
if (!Scopes.VariableExists(context.IDENTIFIER().GetText()) &&
Scopes.LibraryExists(context.IDENTIFIER().GetText()) &&
(context.particle() == null || context.particle().Length == 0))
{
//Library top level call, so don't evaluate like normal particles.
isLibraryTopLevelCall = true;
//Just get the very last function like a normal variable, but from the library.
string libName = context.IDENTIFIER().GetText();
string name = context.functionCall_particle().IDENTIFIER().GetText();
var lib = Scopes.GetLibrary(libName);
if (!lib.VariableExists(name))
{
Error.Fatal(context, "No variable named '" + name + "' exists in library '" + libName + "'.");
return(null);
}
currentVal = lib.GetVariable(name);
}
else
{
//Not a library top level call, so execute like a normal particle block.
currentVal = Particles.ParseParticleBlock(this, context, context.IDENTIFIER(), context.particle());
}
}
else
{
//No particles, just grab the value as an identifier.
string name = context.functionCall_particle().IDENTIFIER().GetText();
if (!Scopes.VariableExists(name))
{
Error.Fatal(context, "No function exists with name '" + name + "'.");
return(null);
}
currentVal = Scopes.GetVariable(name);
}
//Attempt to execute the final function on the result.
if (context.IDENTIFIER() == null || isLibraryTopLevelCall)
{
//Visit and execute THIS value, not a child value (this was a straight normal call).
Particles.SetParticleInput(currentVal);
return(VisitFunctionCall_particle(context.functionCall_particle()));
}
else
{
//There were particles, visit and execute CHILD value.
if (currentVal.Type != AlgoValueType.Object)
{
Error.Fatal(context, "Cannot call a child function on a value with no children (given value was not an object).");
return(null);
}
//Get the child, see if it's a function.
AlgoObject thisObj = currentVal.Value as AlgoObject;
string funcName = context.IDENTIFIER().GetText();
AlgoValue childFunc = thisObj.ObjectScopes.GetVariable(funcName);
if (childFunc == null || (childFunc.Type != AlgoValueType.Function && childFunc.Type != AlgoValueType.EmulatedFunction))
{
Error.Fatal(context, "No child function exists with name '" + funcName + "'.");
return(null);
}
//Set the particle result as the function value, call the function call particle.
Particles.SetParticleInput(childFunc);
return(VisitFunctionCall_particle(context.functionCall_particle()));
}
}