/// <summary>
/// Constructs a DLR Expression tree representing setting a variable inside a context.
/// </summary>
/// <param name="runtime"></param>
/// <param name="variableContainer">The container where the lookup should be performed</param>
/// <param name="contextParts">
/// Contains 2 strings:
/// 1. The name of the context
/// 2. The name of the variable inside the context
/// </param>
/// <param name="value">Expression containing the value of the variable</param>
/// <remarks>
/// The returned DLR Expression tree will try to fetch the context inside the container.
/// If the context does not exists, this will result an exception.
/// If the exception occured, the context will be created inside the catch block.
/// After this the context surely exists, so we can simply set the variable to the provided value.
///
/// </remarks>
/// <returns>>Expression tree for setting a value for the given context parts</returns>
internal static DLR.Expression SetVariable(Aplus runtime, DLR.Expression variableContainer, string[] contextParts, DLR.Expression value)
{
// Get the context
DLR.Expression getContext =
DLR.Expression.TryCatch(
DLR.Expression.Dynamic(
runtime.GetMemberBinder(contextParts[0]),
typeof(object),
variableContainer
),
DLR.Expression.Catch(
// Context not found, create one!
typeof(Error.Value),
DLR.Expression.Dynamic(
runtime.SetMemberBinder(contextParts[0]),
typeof(object),
variableContainer,
DLR.Expression.Constant(new ScopeStorage())
)
)
);
DLR.Expression setVariable = DLR.Expression.Dynamic(
runtime.SetMemberBinder(contextParts[1]),
typeof(object),
getContext,
value
);
return setVariable;
}
/// <summary>
/// Constructs a DLR Expression tree representing setting a variable inside a context.
/// </summary>
/// <param name="runtime"></param>
/// <param name="variableContainer">The container where the lookup should be performed</param>
/// <param name="contextParts">
/// Contains 2 strings:
/// 1. The name of the context
/// 2. The name of the variable inside the context
/// </param>
/// <param name="value">Expression containing the value of the variable</param>
/// <remarks>
/// The returned DLR Expression tree will try to fetch the context inside the container.
/// If the context does not exists, this will result an exception.
/// If the exception occured, the context will be created inside the catch block.
/// After this the context surely exists, so we can simply set the variable to the provided value.
///
/// </remarks>
/// <returns>>Expression tree for setting a value for the given context parts</returns>
internal static DLR.Expression SetVariable(Aplus runtime, DLR.Expression variableContainer, string[] contextParts, DLR.Expression value)
{
// Get the context
DLR.Expression getContext =
DLR.Expression.TryCatch(
DLR.Expression.Dynamic(
runtime.GetMemberBinder(contextParts[0]),
typeof(object),
variableContainer
),
DLR.Expression.Catch(
// Context not found, create one!
typeof(Error.Value),
DLR.Expression.Dynamic(
runtime.SetMemberBinder(contextParts[0]),
typeof(object),
variableContainer,
DLR.Expression.Constant(new ScopeStorage())
)
)
);
DLR.Expression setVariable = DLR.Expression.Dynamic(
runtime.SetMemberBinder(contextParts[1]),
typeof(object),
getContext,
value
);
return(setVariable);
}
/// <summary>
/// Constructs a DLR Expression tree representing accessing a variable inside a context
/// </summary>
/// <param name="runtime"></param>
/// <param name="variableContainer">The container where the lookup should be performed</param>
/// <param name="contextParts">
/// Contains 2 strings:
/// 1. The name of the context
/// 2. The name of the variable inside the context
/// </param>
/// <returns>Expression tree for retrieving a value for the given context parts</returns>
internal static DLR.Expression GetVariable(Aplus runtime, DLR.Expression variableContainer, string[] contextParts)
{
// Get the context
DLR.Expression contextAccess = DLR.Expression.Dynamic(
runtime.GetMemberBinder(contextParts[0]),
typeof(object),
variableContainer
);
// Get the variable from the context
DLR.Expression variableAccess = DLR.Expression.Dynamic(
runtime.GetMemberBinder(contextParts[1]),
typeof(object),
contextAccess
);
return variableAccess;
}
/// <summary>
/// Constructs a DLR Expression tree representing accessing a variable inside a context
/// </summary>
/// <param name="runtime"></param>
/// <param name="variableContainer">The container where the lookup should be performed</param>
/// <param name="contextParts">
/// Contains 2 strings:
/// 1. The name of the context
/// 2. The name of the variable inside the context
/// </param>
/// <returns>Expression tree for retrieving a value for the given context parts</returns>
internal static DLR.Expression GetVariable(Aplus runtime, DLR.Expression variableContainer, string[] contextParts)
{
// Get the context
DLR.Expression contextAccess = DLR.Expression.Dynamic(
runtime.GetMemberBinder(contextParts[0]),
typeof(object),
variableContainer
);
// Get the variable from the context
DLR.Expression variableAccess = DLR.Expression.Dynamic(
runtime.GetMemberBinder(contextParts[1]),
typeof(object),
contextAccess
);
return(variableAccess);
}
public override DLR.Expression Generate(AplusScope scope)
{
DLR.Expression result;
Aplus runtime = scope.GetRuntime();
if (this.Type == IdentifierType.SystemName && runtime.SystemFunctions.ContainsKey(this.Name))
{
// Check if the name is a system function's name and we have such system function
// and return it
result = DLR.Expression.Constant(runtime.SystemFunctions[this.Name]);
return(result);
}
DLR.Expression variableContainer = scope.GetModuleExpression();
string[] contextParts = CreateContextNames(runtime.CurrentContext);
// Check if the scope is a method
if (scope.IsMethod)
{
DLR.Expression parentVariableContainer = scope.Parent.GetModuleExpression();
// Check for variable in method scope
// (maybe the variable is defined in the method header)
DLR.Expression localVariable = scope.FindIdentifier(this.variableName);
if (localVariable != null)
{
// Found a variable defined in the method's header
return(localVariable);
}
if (this.type == IdentifierType.UnQualifiedName)
{
// 1). we check if the variable exists in the function's scope
// 2). check if the variable exits in the current context (error if not found)
//
// if(((IDictionary<String, Object>)($FunctionScope).ContainsKey($VARIABLE))
// {
// return $FunctionScope.$VARIABLE;
// }
// else
// {
// return $GlobalScope.$VARIABLE
// }
//
DLR.Expression getVariable = DLR.Expression.Condition(
DLR.Expression.Call(
DLR.Expression.Convert(variableContainer, typeof(IDictionary <string, object>)),
typeof(IDictionary <string, object>).GetMethod("ContainsKey"),
DLR.Expression.Constant(this.variableName)
),
// True case:
DLR.Expression.Dynamic(
runtime.GetMemberBinder(this.variableName),
typeof(object),
variableContainer
),
// False case:
BuildGlobalAccessor(scope, runtime, parentVariableContainer, contextParts),
// resulting type
typeof(object)
);
result = DLR.Expression.Dynamic(
runtime.ConvertBinder(typeof(AType)),
typeof(AType),
getVariable
);
return(result);
}
else if (this.type == IdentifierType.QualifiedName)
{
// Found a variable like: .var
// for this check the parent's variables
variableContainer = parentVariableContainer;
// Fallback to the non-method case
}
}
result = Tools.CloneMemoryMappedFile(BuildGlobalAccessor(scope, runtime, variableContainer, contextParts));
return(result);
}
