/// <summary>
/// Visit a parse tree produced by <see cref="iroParser.definition"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitDefinition([NotNull] iroParser.DefinitionContext context)
{
return(VisitChildren(context));
}
/// <summary>
/// Returns a variable based on a RHS definition.
/// </summary>
public override IroVariable VisitDefinition([NotNull] iroParser.DefinitionContext context)
{
//Is it an array type?
if (context.ARRAY_SYM() != null)
{
//Yes, must be an identifier or an array on the right.
if (context.definition_ident() != null)
{
//Single value.
var list = new IroList();
list.Add(new IroValue(context.definition_ident().IDENTIFIER().GetText()));
return(list);
}
else if (context.array() != null)
{
//Array, make a list of the items.
var list = new IroList();
foreach (var item in context.array().IDENTIFIER())
{
list.Add(new IroValue(item.GetText()));
}
return(list);
}
else
{
Error.Fatal(context, "An array type is specified, but no array is given for that variable.");
return(null);
}
}
//Regex type?
else if (context.REG_EQUALS_SYM() != null)
{
//Check a regex is used on the right hand side.
if (context.regex() == null)
{
if (context.constant_ref() == null)
{
Error.Fatal(context, "Regular expression equality symbol used, but a regex is not assigned.");
}
else
{
//Return the literal value on the right.
return(new IroReference(context.constant_ref().IDENTIFIER().GetText()));
}
return(null);
}
//Evaluate the regex, return it.
IroRegex regex;
try
{
regex = new IroRegex(context.regex().GetText());
}
catch (Exception e)
{
Error.Fatal(context, "Invalid regular expression created, '" + e.Message + "'.");
return(null);
}
return(regex);
}
//Normal equality type?
else if (context.EQUALS_SYM() != null)
{
//Must be a normal identifier.
if (context.definition_ident() == null)
{
Error.Fatal(context, "Value provided for standard non-regex variable must be a string.");
return(null);
}
//Return the value.
return(new IroValue(context.definition_ident().IDENTIFIER().GetText()));
}
//Unknown.
else
{
Error.Fatal(context, "Unknown definition provided, please submit an issue on the repository with this source grammar included.");
return(null);
}
}
/// <summary>
/// Exit a parse tree produced by <see cref="iroParser.definition"/>.
/// <para>The default implementation does nothing.</para>
/// </summary>
/// <param name="context">The parse tree.</param>
public virtual void ExitDefinition([NotNull] iroParser.DefinitionContext context)
{
}