vgrindefs(5)

NAME

vgrindefs - language definition data base for vgrind(1)

SYNOPSIS

vgrindefs

DESCRIPTION

The vgrindefs file contains all language definitions for

vgrind(1). The
data base is very similar to termcap(5).

FIELDS

The following table names and describes each field.

Name Type Description
ab str regular expression for the start of an

alternate

comment

ae str regular expression for the end of an

alternate

comment

pb str regular expression for start of a pro

cedure
bb str regular expression for start of a lexi

cal block
be str regular expression for the end of a

lexical block
cb str regular expression for the start of a

comment
ce str regular expression for the end of a

comment
sb str regular expression for the start of a

string
se str regular expression for the end of a

string
lb str regular expression for the start of a

character

constant

le str regular expression for the end of a

character

constant

nc str regular expression for a non-comment

(see below)
tl bool present means procedures are only de

fined at the top

lexical level

oc bool present means upper and lower case are

equivalent
kw str a list of keywords separated by spaces

Non-comments are required to describe a certain context

where a sequence
that would normally start a comment loses its special mean

ing. A typical
example for this can be found in Perl, where comments are

normally starting with `#', while the string `$#' is an operator on an ar

ray.

REGULAR EXPRESSIONS

Vgrindefs uses regular expression which are very similar to

those of
ex(1) and lex(1). The characters `^', `$', `:' and `' are

reserved
characters and must be "quoted" with a preceding `' if they

are to be
included as normal characters. The metasymbols and their

meanings are:

$ the end of a line

^ the beginning of a line

a delimiter (space, tab, newline, start of line)

matches any string of symbols (like .* in lex)

matches any alphanumeric name. In a procedure definition (pb)

the string that matches this symbol is used as the

procedure
name.

() grouping

| alternation

? last item is optional

preceding any string means that the string will not

match an

input string if the input string is preceded by an

escape character (. This is typically used for languages (like

C) which can
include the string delimiter in a string by escaping

it.

Unlike other regular expressions in the system, these match

words and not
characters. Hence something like "(tramp|steamer)flies?"

would match
"tramp", "steamer", "trampflies", or "steamerflies".

KEYWORD LIST

The keyword list is just a list of keywords in the language

separated by
spaces. If the "oc" boolean is specified, indicating that

upper and
lower case are equivalent, then all the keywords should be

specified in
lower case.

FILES

/usr/share/misc/vgrindefs File containing terminal descrip

tions.

EXAMPLES

The following entry, which describes the C language, is typ

ical of a language entry.

C|c::pb=^?*????:bb={:be=}:cb=/*:ce=*/:sb=":se=

:lb=':le=':tl: :kw=asm auto break case char continue default

do double else enum extern float for fortran goto if int long

register return short sizeof static struct switch typedef

union unsigned while #define #else #endif #if #ifdef #ifndef

#include #undef # define else endif if ifdef ifndef include

undef:

Note that the first field is just the language name (and any

variants of
it). Thus the C language could be specified to vgrind(1) as

"c" or "C".

Entries may continue onto multiple lines by giving a as the

last character of a line. Capabilities in vgrindefs are of two

types: Boolean
capabilities which indicate that the language has some par

ticular feature
and string capabilities which give a regular expression or

keyword list.

SEE ALSO

troff(1), vgrind(1)

HISTORY

The vgrindefs file format appeared in 4.2BSD.

BSD June 6, 1993

BSD