public virtual LangElement HeredocExpression(Span span, LangElement expression, Tokens quoteStyle, Lexer.HereDocTokenValue heredoc)
{
Debug.Assert(heredoc != null);
switch (quoteStyle)
{
case Tokens.T_SINGLE_QUOTES:
return(new NowDocExpression(span, (Expression)expression, heredoc.Label));
default:
return(new HereDocExpression(span, (Expression)expression, heredoc.Label, quoteStyle == Tokens.T_DOUBLE_QUOTES));
}
}
/// <summary>
/// Traverse through the expression (either <see cref="IStringLiteralValue"/> or concat of <see cref="IStringLiteralValue"/>s),
/// and checks and removes the leading whitespace indentation.
/// </summary>
/// <param name="element">Either <see cref="IStringLiteralValue"/> or <see cref="IConcatEx"/> with <see cref="IStringLiteralValue"/>s.</param>
/// <param name="heredoc">Heredoc information.</param>
/// <param name="lineBegin">Whether the element starts at line beginning.</param>
LangElement RemoveHereDocIndentation(LangElement element, Lexer.HereDocTokenValue heredoc, bool lineBegin)
{
var indentation = heredoc.Indentation.AsSpan();
if (indentation.IsEmpty)
{
return element;
}
if (!indentation.IsWhiteSpace())
{
throw new ArgumentException("", nameof(indentation));
}
//
if (element is ConcatEx concat)
{
var parts = concat.Expressions;
for (int i = 0; i < parts.Length; i++)
{
parts[i] = (Expression)RemoveHereDocIndentation(parts[i], heredoc, lineBegin && i == 0);
}
}
else if (element is IStringLiteralValue str) // i.e. StringLiteral
{
// if (str.Contains8bitText) // TODO, use str.EnumerateChunks() : byte[]|string
var content = str.ToString();
var result = StringUtils.GetStringBuilder(content.Length);
var errorreported = false;
foreach (var lineSpan in TextUtils.EnumerateLines(content, true))
{
if (lineBegin)
{
var lineText = content.AsSpan(lineSpan.Start, lineSpan.Length);
if (lineText.StartsWith(indentation))
{
result.Append(content, lineSpan.Start + indentation.Length, lineSpan.Length - indentation.Length);
continue;
}
else if (lineText.IsWhiteSpace())
{
// allowed, empty line
// add the line break
result.Append(lineText.TrimStart(" \t".AsSpan()).ToString());
continue;
}
else if (!errorreported)
{
// error
_errors.Error(element.Span, FatalErrors.HeredocIndentError);
errorreported = true; // report error just once
}
}
// next lines are from the line begin
lineBegin = true;
result.Append(content, lineSpan.Start, lineSpan.Length);
}
return new StringLiteral(element.Span, StringUtils.ReturnStringBuilder(result));
}
return element;
}
public override LangElement HeredocExpression(Span span, LangElement expression, Tokens quoteStyle, Lexer.HereDocTokenValue heredoc) => CountLE(base.HeredocExpression(span, expression, quoteStyle, heredoc));
