1 files changed, 0 insertions, 45 deletions
diff --git a/spec/grammar/parser/syntax_error.go b/spec/grammar/parser/syntax_error.go
deleted file mode 100644
index 719fb94..0000000
--- a/spec/grammar/parser/syntax_error.go
+++ /dev/null
@@ -1,45 +0,0 @@
-package parser
-
-type SyntaxError struct {
-	message string
-}
-
-func newSyntaxError(message string) *SyntaxError {
-	return &SyntaxError{
-		message: message,
-	}
-}
-
-func (e *SyntaxError) Error() string {
-	return e.message
-}
-
-var (
-	// lexical errors
-	synErrIDInvalidChar            = newSyntaxError("an identifier can contain only the lower-case letter, the digits, and the underscore")
-	synErrIDInvalidUnderscorePos   = newSyntaxError("the underscore cannot be placed at the beginning or end of an identifier")
-	synErrIDConsecutiveUnderscores = newSyntaxError("the underscore cannot be placed consecutively")
-	synErrIDInvalidDigitsPos       = newSyntaxError("the digits cannot be placed at the biginning of an identifier")
-	synErrUnclosedTerminal         = newSyntaxError("unclosed terminal")
-	synErrUnclosedString           = newSyntaxError("unclosed string")
-	synErrIncompletedEscSeq        = newSyntaxError("incompleted escape sequence; unexpected EOF following a backslash")
-	synErrEmptyPattern             = newSyntaxError("a pattern must include at least one character")
-	synErrEmptyString              = newSyntaxError("a string must include at least one character")
-
-	// syntax errors
-	synErrInvalidToken           = newSyntaxError("invalid token")
-	synErrTopLevelDirNoSemicolon = newSyntaxError("a top-level directive must be followed by ;")
-	synErrNoProductionName       = newSyntaxError("a production name is missing")
-	synErrNoColon                = newSyntaxError("the colon must precede alternatives")
-	synErrNoSemicolon            = newSyntaxError("the semicolon is missing at the last of an alternative")
-	synErrLabelWithNoSymbol      = newSyntaxError("a label must follow a symbol")
-	synErrNoLabel                = newSyntaxError("an identifier that represents a label is missing after the label marker @")
-	synErrNoDirectiveName        = newSyntaxError("a directive needs a name")
-	synErrNoOrderedSymbolName    = newSyntaxError("an ordered symbol name is missing")
-	synErrUnclosedDirGroup       = newSyntaxError("a directive group must be closed by )")
-	synErrPatternInAlt           = newSyntaxError("a pattern literal cannot appear directly in an alternative. instead, please define a terminal symbol with the pattern literal")
-	synErrStrayExpOp             = newSyntaxError("an expansion operator ... must be preceded by an identifier")
-	synErrInvalidExpOperand      = newSyntaxError("an expansion operator ... can be applied to only an identifier")
-	synErrSemicolonNoNewline     = newSyntaxError("a semicolon must be followed by a newline")
-	synErrFragmentNoPattern      = newSyntaxError("a fragment needs one pattern element")
-)