/// <summary>
/// Tries to get the external variable based on the stored reference
/// and will return the evaluation result of the looked up object if possible.
/// Returns <c>null</c> in case the variable could not be found or the evaluation
/// of the looked up variable returned <c>null</c>.
/// </summary>
public override L20nObject Eval(LocaleContext ctx, params L20nObject[] argv)
{
var variable = ctx.GetVariable(m_Identifier);
if (variable == null)
{
return variable;
}
return variable.Eval(ctx, argv);
}
/// <summary>
/// A help function to get the entity based on the first variable.
/// The given identifier is either an Identifier, Variable or Global,
/// which will define the action to be taken in order to get and return the Root Entity.
/// </summary>
private Entity GetEntity(LocaleContext ctx)
{
// is it an identifier?
var identifier = m_Root as Identifier;
if (identifier != null)
return ctx.GetEntity(identifier.Value);
// is it a string?
var str = m_Root.Eval(ctx) as StringOutput;
if (str != null)
return ctx.GetEntity(str.Value);
// is it a variable?
var variable = m_Root as Variable;
if (variable != null)
return ctx.GetVariable(variable.Identifier) as Entity;
// is it a global?
var global = m_Root as Global;
if (global != null)
return ctx.GetGlobal(global.Identifier) as Entity;
return null;
}
/// <summary>
/// A help function to get the root entity based on the first variable.
/// The given identifier is either an Identifier, Variable or Global,
/// which will define the action to be taken in order to get and return the Root Entity.
/// </summary>
private Entity GetEntity(LocaleContext ctx, L20nObject key)
{
// is it an identifier?
var identifier = key as Identifier;
if (identifier != null)
return ctx.GetEntity(identifier.Value);
// is it a variable?
var variable = key as Variable;
if (variable != null)
{
var obj = ctx.GetVariable(variable.Identifier);
// a variable can also be a string-reference to an entity
var reference = obj as StringOutput;
if (reference != null)
{
return ctx.GetEntity(reference.Value);
}
// otherwise it's simply an entity (or at least it should be)
return obj as Entity;
}
// is it a global?
var global = key as Global;
if (global != null)
return ctx.GetGlobal(global.Identifier) as Entity;
// is it a string?
var str = key as StringOutput;
if (str != null)
return ctx.GetEntity(str.Value);
return null;
}