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Diffstat (limited to 'Doc/ref1.tex')
| -rw-r--r-- | Doc/ref1.tex | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/Doc/ref1.tex b/Doc/ref1.tex index b373e36..169c244 100644 --- a/Doc/ref1.tex +++ b/Doc/ref1.tex @@ -43,22 +43,22 @@ name: lc_letter (lc_letter | "_")* lc_letter: "a"..."z" \end{verbatim} -The first line says that a \verb\name\ is an \verb\lc_letter\ followed by -a sequence of zero or more \verb\lc_letter\s and underscores. An -\verb\lc_letter\ in turn is any of the single characters `a' through `z'. +The first line says that a \verb@name@ is an \verb@lc_letter@ followed by +a sequence of zero or more \verb@lc_letter@s and underscores. An +\verb@lc_letter@ in turn is any of the single characters `a' through `z'. (This rule is actually adhered to for the names defined in lexical and grammar rules in this document.) Each rule begins with a name (which is the name defined by the rule) -and a colon. A vertical bar (\verb\|\) is used to separate +and a colon. A vertical bar (\verb@|@) is used to separate alternatives; it is the least binding operator in this notation. A -star (\verb\*\) means zero or more repetitions of the preceding item; -likewise, a plus (\verb\+\) means one or more repetitions, and a -phrase enclosed in square brackets (\verb\[ ]\) means zero or one +star (\verb@*@) means zero or more repetitions of the preceding item; +likewise, a plus (\verb@+@) means one or more repetitions, and a +phrase enclosed in square brackets (\verb@[ ]@) means zero or one occurrences (in other words, the enclosed phrase is optional). The -\verb\*\ and \verb\+\ operators bind as tightly as possible; +\verb@*@ and \verb@+@ operators bind as tightly as possible; parentheses are used for grouping. Literal strings are enclosed in -double quotes. White space is only meaningful to separate tokens. +quotes. White space is only meaningful to separate tokens. Rules are normally contained on a single line; rules with many alternatives may be formatted alternatively with each line after the first beginning with a vertical bar. @@ -66,7 +66,7 @@ first beginning with a vertical bar. In lexical definitions (as the example above), two more conventions are used: Two literal characters separated by three dots mean a choice of any single character in the given (inclusive) range of ASCII -characters. A phrase between angular brackets (\verb\<...>\) gives an +characters. A phrase between angular brackets (\verb@<...>@) gives an informal description of the symbol defined; e.g. this could be used to describe the notion of `control character' if needed. \index{lexical definitions} |