unoplatform/uno · error · Exception

Expected digits after floating point.

Error message

Expected digits after floating point.

What it means

When parsing a numeric literal argument in x:Bind, a '.' is treated as the start of a fractional part and must be followed by at least one digit. A '.' with no following digit (e.g. '3.') throws. Example trigger: {x:Bind Foo(3.)}.

Source

Thrown at src/SourceGenerators/Uno.UI.SourceGenerators/XamlGenerator/Utils/XBindExpressionParser.CoreParser.cs:124

				var literal = _xBind.Substring(oldPosition, ++_position - oldPosition);
				return new XBindLiteralArgument() { LiteralArgument = literal };
			}
			else if (char.IsDigit(Current))
			{
				// literal numeric argument
				var oldPosition = _position;
				while (char.IsDigit(Current))
				{
					_position++;
				}

				if (Current == '.')
				{
					_position++;
					if (!char.IsDigit(Current))
					{
						throw new Exception("Expected digits after floating point.");
					}

					while (char.IsDigit(Current))
					{
						_position++;
					}
				}

				var literal = _xBind.Substring(oldPosition, _position - oldPosition);
				return new XBindLiteralArgument() { LiteralArgument = literal };
			}

			return new XBindPathArgument() { Path = ParseXBindPath() };
		}

		private void SkipWhitespaces()
		{
			while (char.IsWhiteSpace(Current))

View on GitHub (pinned to 0418340488)

Solutions

1. Provide at least one digit after the '.', e.g. 3.0 instead of 3.
2. Drop the '.' if an integer was intended.

Example fix

<!-- before -->
<TextBlock Text="{x:Bind Scale(3.)}" />
<!-- after -->
<TextBlock Text="{x:Bind Scale(3.0)}" />

// Lint rule: a '.' inside a numeric x:Bind argument must be followed by a digit.
static bool FractionWellFormed(string num)
{ int i = num.IndexOf('.'); return i < 0 || (i + 1 < num.Length && char.IsDigit(num[i + 1])); }

When it happens

Trigger: A numeric x:Bind argument ends in '.' with no fractional digits, e.g. {x:Bind Foo(3.)} or {x:Bind Foo(.5)} when the integer portion is absent is handled separately, but '3.' specifically triggers this.

Common situations: Typo in a numeric x:Bind literal; trailing decimal point.

Related errors

• Expected end of x:Bind expression or start of argument list.
• Expected end of expression after invocation.
• Expected ')' after parsing invocation arguments
• Missing closing quote
• Missing parenthesis?

AI-assisted analysis of unoplatform/uno@0418340488 (2026-08-13). Data as JSON: /api/errors/75f3061be87bbf52. Report an issue: GitHub.