The following listing contains a BNF (Backus Naur Form) description of the
User Language source code syntax. Comments are delimited by
/* and
*/. The colon
(:) corresponds with an assignment operator and is to be read as "is composed of". The vertical line
(|) designates alternatives and is to be read as "or". Identifiers are denoted by the
IDENT symbol, constants are marked by
NUMBER (numeric),
SQSTR (character) and
DQSTR (string), respectively. The
EOLN symbols defines the end-of-line control character. Boldfaced words or character sequences represent the terminal symbols (reserved words and/or operators).
/* User Language Source Code Syntax */
/* Program definition */
program
: progdefs
;
progdefs
: progdefs progdef
|
;
progdef
: preproccmd
| typedef
| storageclass vardef
| storageclass fctdef
;
/* Preprocessor command */
preproccmd
: #include DQSTR EOLN
| #define IDENT optexpr EOLN
| #undef IDENT EOLN
| #if expression EOLN
| #ifdef IDENT EOLN
| #ifndef IDENT EOLN
| #else EOLN
| #endif EOLN
| #bnf { syntaxdef }
| #pragma pragmaval
;
pragmaval
: ULCALLERSTD
| ULCALLERCAP
| ULCALLERSCM
| ULCALLERLAY
| ULCALLERGED
| ULCALLERAR
| ULCALLERCAM
| ULCALLERCV
| ULCALLERICD
| ULCALLERCED
| ULCALLERNOUNDO
;
/* Type definition */
typedef
: typedef declaration
;
/* Variable definition */
vardef
: typespec initdecs ;
;
/* Function definition */
fctdef
: fcttype IDENT ( fctpars ) fctpardecs { cmditems } ;
fcttype
: typespec
| void
|
;
fctpars
: fctpardefs
|
;
fctpardefs
: fctpardefs , IDENT
| IDENT
;
fctpardecs
: fctpardecs vardef
|
;
/* Storage class */
storageclass
| static
| structdef
;
/* Type specification */
typespec
: int
| double
| char
| string
| index IDENT
| structdef
| IDENT
;
/* Struct definition */
structdef
: struct IDENT
| struct IDENT { members }
| struct { members }
;
members
: members declaration
| declaration
;
/* Declaration */
declaration
: typespec decs ;
;
decs
: decs , declarator
| declarator
;
/* Initialized declarator list */
initdecs
: initdecs , initdec
| initdec
|
;
initdec
: declarator
| declarator = initializer
;
/* Declarator */
declarator
: IDENT
| declarator [ ]
;
/* Initializer */
initializer
: assignment
| { initializers }
;
initializers
: initializers , initializer
| initializer
;
/* Command block */
cmdblock
: { cmditems }
| cmditem
;
/* Command list */
cmditems
: cmditems cmditem
|
;
/* Command item */
cmditem
: preproccmd
| typedef
| vardef
| ifcmd
| switchcmd
| forcmd
| whilecmd
| docmd
| forallcmd
| return optexpr ;
| break ;
| continue ;
| optexpr ;
;
/* If control structure */
ifcmd
: if ( expression ) cmdblock elsecmd
;
elsecmd
: else cmdblock
|
;
/* Switch control structure */
switchcmd
: switch ( expression ) { caseblocks }
;
caseblocks
: caseblocks caseblock
|
;
caseblock
: cases cmditems
;
cases
: cases case
| case
;
case
: case expression :
| default :
;
/* For control structure */
forcmd
: for ( optexpr ; optexpr ; optexpr ) cmdblock
;
/* While control structure */
whilecmd
: while ( expression ) cmdblock
;
/* Do control structure */
docmd
: do cmdblock while ( expression ) ;
;
/* Forall control structure */
forallcmd
: forall ( IDENT forallof forallwhere ) cmdblock
;
forallof
: of IDENT
|
;
forallwhere
: where expression
|
;
/* Expression */
optexpr
: expression
|
;
expression
: expression , assignment
| assignment
;
/* Assignment */
assignment
: unary = assignment
| unary |= assignment
| unary ^= assignment
| unary &= assignment
| unary <<= assignment
| unary >>= assignment
| unary += assignment
| unary -= assignment
| unary *= assignment
| unary /= assignment
| unary %= assignment
| conditional
;
/* Conditional evaluation */
conditional
: log_or
| log_or ? conditional : conditional
;
/* Logical OR */
log_or
: log_and
| log_and || log_or
;
/* Logical AND */
log_and
: bit_or
| bit_or && log_and
;
/* Bit OR */
bit_or
: bit_xor
| bit_or | bit_xor
;
/* Bit Exclusive OR */
bit_xor
: bit_and
| bit_xor ^ bit_and
;
/* Bit AND */
bit_and
: equality
| bit_and & equality
;
/* Equivalence comparison */
equality
: comparison
| equality == comparison
| equality != comparison
;
/* Comparison */
comparison
: shift
| comparison < shift
| comparison <= shift
| comparison > shift
| comparison >= shift
;
/* Shift operations */
shift
: sum
| shift << sum
| shift >> sum
;
/* Addition and substraction */
sum
: product
| sum + product
| sum - product
;
/* Multiplication and division */
product
: unary
| product * unary
| product / unary
| product % unary
;
/* Unary operators */
unary
: primary
| primary ++
| primary --
| - unary
| ! unary
| ~ unary
| ++ unary
| -- unary
;
/* Primary operators */
primary
: IDENT
| NUMBER
| SQSTR
| DQSTR
| ( expression )
| IDENT ( optexpr )
| primary [ expression ]
| primary . IDENT
;
/* BNF Precompiler syntax definition */
syntaxdef
: commentdef grammar
;
commentdef
: COMMENT ( commentdel commentend ) ;
|
;
commentend
: , commentdel
|
;
commentdel
: SQSTR
| DQSTR
;
grammar
: grammar rule
| rule
;
rule
: IDENT : forms ;
| IDENT : forms | ;
;
forms
: form | forms
| form
;
form
: form symbol action
| symbol action
;
symbol
: IDENT
| SQSTR
| DQSTR
| IDENT
| NUMBER
| SQSTR
| DQSTR
| EOLN
| EOF
| EOFINC
| UNKNOWN
;
action
| ( IDENT ( NUMBER ) )
| ( IDENT )
|
;
/* BNF syntax description file end */
Syntax Definition
© 1985-2025 Oliver Bartels F+E
