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Enhance context output of UnexpectedToken exception

Open ohader opened this issue 5 years ago • 0 comments

Grammar

%pragma		parser.lookahead 	0
%skip		space				\s
%token      int                 \d+
%token      div                 /           -> div
%token      div:int             [1-9]\d*    -> __shift__ * 1
%token      mul                 \*          -> mul
%token      mul:int             \d+         -> __shift__ * 1
#root:
    <int> ( ::mul:: <int> #multiply | ::div:: <int> #divide )*

// this line is superfluous
%token      mul:mul             \*

Source

1**1

Results

Parsing above scenario leads to expected exception, since lexeme * is not allowed in rules. In thrown UnexpectedToken

  • the namespace of the corresponding token could be mentioned (helpful when having multiple namespaces using same token identifiers)
Hoa\Compiler\Exception\UnexpectedToken: Unexpected token "*" (mul) at line 1 and column 3:
1**1
  ↑ in /Users/olly/Development/Packages/fluid-compiler/vendor/hoa/compiler/Llk/Parser.php on line 1

With adjustments

Hoa\Compiler\Exception\UnexpectedToken: Unexpected token "*" (mul:mul) at line 1 and column 3:
1**1
  ↑ in /Users/olly/Development/Packages/fluid-compiler/vendor/hoa/compiler/Llk/Parser.php on line 1

ohader avatar Oct 06 '20 10:10 ohader