mirror of
https://github.com/fadden/6502bench.git
synced 2024-12-29 08:29:52 +00:00
79 lines
3.2 KiB
C#
79 lines
3.2 KiB
C#
/*
|
|
* Copyright 2018 faddenSoft
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
using System;
|
|
using System.Text.RegularExpressions;
|
|
|
|
namespace Asm65 {
|
|
/// <summary>
|
|
/// Utility classes for working with labels.
|
|
///
|
|
/// The decision of whether to treat labels as case-sensitive or case-insensitive is
|
|
/// encapsulated here. All code should be case-preserving, but the comparison method
|
|
/// and "normal form" are defined here.
|
|
/// </summary>
|
|
public class Label {
|
|
// Arbitrary choice for SourceGen. Different assemblers have different limits.
|
|
public const int MAX_LABEL_LEN = 32;
|
|
|
|
public const bool LABELS_CASE_SENSITIVE = true;
|
|
|
|
/// <summary>
|
|
/// String comparer to use when comparing labels.
|
|
///
|
|
/// We may want case-insensitive string compares, and we want the "invariant culture"
|
|
/// version for consistent results across users in multiple locales. (The labels are
|
|
/// expected to be ASCII strings, so the latter isn't crucial unless we change the
|
|
/// allowed set.)
|
|
/// </summary>
|
|
public static readonly StringComparer LABEL_COMPARER = LABELS_CASE_SENSITIVE ?
|
|
StringComparer.InvariantCulture :
|
|
StringComparer.InvariantCultureIgnoreCase;
|
|
|
|
/// <summary>
|
|
/// Regex pattern for a valid label.
|
|
///
|
|
/// ASCII-only, starts with letter or underscore, followed by at least
|
|
/// one alphanumeric or underscore. Some assemblers may allow single-letter
|
|
/// labels, but I don't want to risk confusion with A/S/X/Y. So either we
|
|
/// reserve those, or we just mandate a two-character minimum.
|
|
/// </summary>
|
|
private static string sValidLabelPattern = @"^[a-zA-Z_][a-zA-Z0-9_]+$";
|
|
private static Regex sValidLabelCharRegex = new Regex(sValidLabelPattern);
|
|
|
|
/// <summary>
|
|
/// Validates a label, confirming that it is correctly formed.
|
|
/// </summary>
|
|
/// <param name="label">Label to validate.</param>
|
|
/// <returns>True if the label is correctly formed.</returns>
|
|
public static bool ValidateLabel(string label) {
|
|
if (label.Length > MAX_LABEL_LEN) {
|
|
return false;
|
|
}
|
|
MatchCollection matches = sValidLabelCharRegex.Matches(label);
|
|
return matches.Count == 1;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Returns "normal form" of label. This matches LABEL_COMPARER behavior.
|
|
/// </summary>
|
|
/// <param name="label">Label to transform.</param>
|
|
/// <returns>Transformed label.</returns>
|
|
public static string ToNormal(string label) {
|
|
return LABELS_CASE_SENSITIVE ? label : label.ToUpperInvariant();
|
|
}
|
|
}
|
|
}
|