skipper = (([ \t\n\r\b]|\#[^\n\r]*|\\[\r\n])+|\b)

any = [^]
name = (?i:[a-z_][a-z0-9_]*)
filename = (?i:([.a-z0-9_]|\\[^])*)
accname = {-name}(::{-name})*
inum = [1248]
rnum = [48]
cnum = 8|16
type = (void|CCTK_INT{inum}?|CCTK_REAL{rnum}?|CCTK_COMPLEX{cnum}?|CCTK|CCTK_POINTER|CCTK_TO_CONST)

num = [0-9]+
boolraw = (?i:true|t|yes|y|false|f|no|n|1|0)
bool = {-boolraw}|"{-boolraw}"

powexpr = \( {expr} \)|-{expr}|{accname}|{num}
mulexpr = {powexpr}( \^ {powexpr})?
mulop = [/*%]
addexpr = {mulexpr}( {mulop} {mulexpr})*
addop = [+-]
expr = {addexpr}( {addop} {addexpr})*
n = ([\ \t]|\\[\r\n])*

IMPLEMENTS = (?i:implements):{-n}{name}
INHERITS = (?i:inherits):{-n}({name}({-n},?{-n}{name})*)?
FRIEND = (?i:friend):{-n}({name}({-n},?{-n}{name})*)?

what = (?i:SOURCE|HEADER)
INCLUDE = (?i:INCLUDE(S)? {what}?: {filename} in {filename})

ret_type = (?i:void|CCTK_INT{num}?|CCTK_REAL|CCTK_COMPLEX|CCTK_POINTER_TO_CONST|CCTK_POINTER)
arg_type = (?i:CCTK_STRING|CCTK_INT{num}?|CCTK_REAL|CCTK_COMPLEX|CCTK_POINTER_TO_CONST|CCTK_POINTER|STRING)
intent = (?i:INOUT|OUT|IN)
array = (?i:array)
fpointer = ({intent} (?i:CCTK_FPOINTER)|(?i:CCTK_FPOINTER) {intent}|(?i:CCTK_FPOINTER)) {name} {args}
arg = {arg_type} ({fpointer}|{array} {intent} {name}|{intent} {array} {name}|{intent} {name})
args = \( ({arg}( , {arg})* )?\)

FUNCTION_ALIAS = (?i:{ret_type} FUNCTION | SUBROUTINE ) {name} {args}
FUNCTION_PTR = (?i:CCTK_FPOINTER {name} \( {arg_type} {intent} {name} (, {arg_type} {intent} {name} )*\))
REQUIRES_FUN = (?i:REQUIRES FUNCTION {name})
USES_FUN = (?i:USES FUNCTION {name}|USES INCLUDE {what}?: {filename}([ \t]+{filename})*)
PROVIDES_FUN = (?i:PROVIDES FUNCTION {name} WITH {name} LANGUAGE (?i:C|FORTRAN))
FUNCTION = ({FUNCTION_ALIAS}|{FUNCTION_PTR}|{REQUIRES_FUN}|{USES_FUN}|{PROVIDES_FUN})

access = (?i:protected|public|private)
vtype = (?i:(CHAR|BYTE|INT{inum}?|REAL{rnum}?|COMPLEX{cnum}?))
VARS = ({name}( ,? {name} )*)( ,)?
gtype = (?i:GF|ARRAY|SCALAR)
dim = {-num}
timelevels = {-num}
size = {expr}( , {expr})*|" {expr}( , {expr})* "
distrib = (?i:CONSTANT|DEFAULT)
ghostsize = {-size}
stagger = (?i:[MCP](,[MCP])*)
tags = {-quote}

GROUP_VARS = (?i:CCTK_|){vtype} {name}( \[ {expr} \])? (?i:TYPE = {gtype} | DIM = {dim} | 
             TIMELEVELS = {timelevels} | SIZE = {size} | DISTRIB = {distrib} | 
             GHOSTSIZE = {ghostsize} | STAGGER = {stagger} | TAGS = {tags})* {dquote}? (
 \{
    {VARS}
 \} {dquote}?
 )?
 

FUNC_GROUP = ({FUNCTION} |{access}: |{GROUP_VARS} |{INCLUDE} |{IMPLEMENTS} |{INHERITS} |{FRIEND} )

dquote = "(\\{-any}|[^"])*"
squote = '(\\{-any}|[^'])*'
quote = {dquote}|{squote}

intr = ^(?i: {FUNC_GROUP}*)$