DEFINITION | DIV | DO | ELSE | ELSIF | END | EXIT | FOR | FROM | GENLIB | IF |
  IMPLEMENTATION | IMPORT | IN | LOOP | MOD | MODULE | NEW | NONE | NOT | OF |
  OPAQUE | OR | POINTER | PROCEDURE | RECORD | REFERENTIAL | RELEASE | REPEAT |
  RETAIN | RETURN | SET | THEN | TO | TYPE | UNTIL | VAR | WHILE | YIELD

  '.' | ',' | ':' | ';' | '|' | '~' | '..' | ':=' |  |  |
  '::' | '+' | '-' | '*' | '/' | '\' | '&' | '^' |

@]

#3.4 Template Language Symbols

#3.3 Pragma Punctuation and Delimiters

Res Word? :=

Dual Use Ident? :=

Special Symbol? :=

Ident :=

Std Lib Ident? :=

Letter Or Digit? :=

Foreign Ident Char? :=

Ident Tail Char? :=

Number Literal? :=

Decimal Number Tail? :=

Real Number Tail? :=

Digit Seq? :=

Base 16 Digit Seq? :=

Base 2 Digit Seq? :=

Digit :=

Base 16 Digit? :=

Base 2 Digit? :=

Digit Sep? := "'" ;

String Literal? :=

Single Quoted String? :=

Double Quoted String? :=

Quotable Character? :=

Letter :=

Space := ' ' ;

Non Alpha Num Quotable? :=

Escaped Character? :=

Chevron Text? :=

@]

<< Non Terminals | Ignore Symbols >>

@]

#4 Identifier   syntax diagram

#4.1 Standard Library Identifier   syntax diagram

#4.2 Letter Or Digit   syntax diagram

#4.3 Foreign Identifier Character   syntax diagram

#4.4 Identifier Tail Character   syntax diagram

#5 Number Literal   syntax diagram

#5.1 Decimal Number Tail   syntax diagram

#5.2 Real Number Tail   syntax diagram

#5.3 Digit Sequence   syntax diagram

#5.4 Base-16 Digit Sequence   syntax diagram

#5.5 Base-2 Digit Sequence   syntax diagram

#5.6 Digit   syntax diagram

#5.7 Base-16 Digit   syntax diagram

#5.8 Base-2 Digit   syntax diagram

#6 String Literal   syntax diagram

#6.1 Single Quoted String   syntax diagram

#6.2 Double Quoted String   syntax diagram

#6.3 Quotable Character   syntax diagram

#6.4 Letter   syntax diagram

#6.6 Non-Alphanumeric Quotable   syntax diagram

#6.7 Escaped Character   syntax diagram

#7 Chevron Text   syntax diagram

#2 Dual-Use Identifiers
(Schrödinger's Tokens)

Special Symbol? :

  '::' | '+' | '-' | '*' | '*.' | '/' | '\' | '&' |
  '=' | '#' | '>' | '>=' | '<' | '<=' | '==' |
  >' | '<>' | '><' | '+/ |
  '(' | ')' | '[' | ']' | '{' | '}'

  '.' | ',' | ':' | ';' | '|' | '^' | '~' | '..' | ':=' |  |  |

  '.' | ',' | ':' | ';' | '|' | '^' | '~' | '..' | ':=' |  | '--" |
  '::' | '+' | '-' | '*' | '*.' | '/' | '\' | '=' | '#' | '>' | '>=' | '<' | '<=' | '==' | '&' |
  >' | '<>' | '><' | '+/ | '(' | ')' | '[' | ']' | '{' | '}'

ResWord :
  ALIAS | AND | ARGLIST | ARRAY | BEGIN | BLUEPRINT | BY | CASE | CONST | COPY |
  DEFINITION | DIV | DO | ELSE | ELSIF | END | ENUM | EXIT | FOR | FROM | GENLIB |
  IF | IMPLEMENTATION | IMPORT | IN | LOOP | MOD | MODULE | NEW | NONE | NOT |
  OF | OPAQUE | OR | POINTER | PROCEDURE | RECORD | REFERENTIAL | RELEASE |
  REPEAT | RETAIN | RETURN | SET | THEN | TO | TYPE | UNTIL | VAR | WHILE | YIELD
  ;

DualUseIdent :
  ABS | ADDRESS | APPEND | CAST | COUNT | COROUTINE | EXISTS | INSERT |
  LENGTH | OCTET | READ | READNEW | REMOVE | SEEK | STORE | SUBSET | SXF |
  TDYN | TFLAGS | TLIMIT | TLITERAL | TMAX | TMIN | TORDERED | TREFC |
  TSCALAR | TSORTED | UNSAFE | VAL | VALUE | WRITE | WRITEF
  ;

SpecialSymbols :
  '.' | ',' | ':' | ';' | '|' | '^' | '~' | '..' | ':=' | '++' | '--" | '::' | '+' | '-' | '*' | '*.' | '/' | '\' |
  '=' | '#' | '>' | '>=' | '<' | '<=' | '==' | '&' | '->' | '<>' | '><' | '+/-' |
  '(' | ')' | '[' | ']' | '{' | '}'
  ;

#1 Reserved Words

ALIAS, AND, ARGLIST, ARRAY, BEGIN, BLUEPRINT, BY,CASE, CONST, COPY, DEFINITION, DIV, DO, ELSE, ELSIF, END, ENUM, EXIT, FOR, FROM, IF, IMPLEMENTATION, IMPORT, IN, LOOP, MOD, MODULE, NEW, NONE, NOT, OF, OPAQUE, OR, POINTER, PROCEDURE, RECORD, REFERENTIAL, RELEASE, REPEAT, RETAIN, RETURN, SET, THEN, TO, TYPE, UNTIL, VAR, WHILE, YIELD

#2 Dual-Use Identifiers (Schrödinger's Tokens)

ABS, ADDRESS, APPEND, CAST, COUNT, COROUTINE, EXISTS, INSERT, LENGTH, OCTET, READ, READNEW, REMOVE, SEEK, STORE, SUBSET, SXF, TDYN, TFLAGS, TLIMIT, TLITERAL, TMAX, TMIN, TORDERED, TREFC, TSCALAR, TSORTED, UNSAFE, VAL, VALUE, WRITE, WRITEF

#3 Special Symbols

.   ,   :   ;   |   ^   ~   ..   :=   ++   --   ::   +   -   *   *.   /   \   =   #   >   >=   <   <=   ==   &   ->   <>   ><   +/-   (   )   [   ]   {   }  

#3.1 Quoted Text Delimiters

'   "   <<   >>  

#3.2 Comment Delimiters

!   (*   *)  

#3.3 Pragma Affix and Delimiters

?   <*   *>  

#3.3 Template Language Symbols

##   <#   #>   @@   //   /*   */  

#3.5 Reserved Symbols

`   for use as a token by Objective Modula-2
@   for use as a lead character in identifiers and reserved words by language supersets
%   for use as a character in identifiers and reserved words by implementations targetingOpenVMS

#4 Identifier

Ident :
  ( Letter | ForeignIdentChar+ LetterOrDigit+ ) IdentTailChar*
  ;

#4.1 Standard Library Identifier

StdLibIdent :
  Letter LetterOrDigit*
  ;

#4.2 Letter Or Digit

LetterOrDigit :
  Letter | Digit
  ;

#4.3 Foreign Identifier Character

ForeignIdentChar :
  '_' | '$'
  ;

#4.4 Identifier Tail Character

IdentTailChar :
  LetterOrDigit | ForeignIdentChar
  ;

#5 Number Literal

NumberLiteral :
  /* number literals starting with digit 0 ... */
  '0' (
    /* without prefix are real numbers */
    RealNumberTail |
    /* with prefix 0b are base-2 numbers */
    'b' Base2DigitSeq |
    /* with prefix 0x are base-16 numbers */
    'x' Base16DigitSeq |
    /* with prefix 0u are unicode code points */
    'u' Base16DigitSeq
  )?
  /* number literals starting with digits 1 to 9 ... */
  | '1'..'9' DecimalNumberTail? /* are always decimal numbers */
  ;

#5.1 Decimal Number Tail

DecimalNumberTail :
  DigitSep? DigitSeq RealNumberTail? | RealNumberTail
  ;

#5.2 Real Number Tail

RealNumberTail :
  '.' DigitSeq ( 'e' ( '+' | '-' )? DigitSeq )?
  ;

#5.3 Digit Sequence

DigitSeq :
  Digit+ ( DigitSep Digit+ )*
  ;

#5.4 Base-16 Digit Sequence

Base16DigitSeq :
    Base16Digit+ ( DigitSep Base16Digit+ )*
    ;

#5.5 Base-2 Digit Sequence

Base2DigitSeq :
  Base2Digit+ ( DigitSep Base2Digit+ )*
  ;

#5.6 Digit

Digit :
  Base2Digit | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
  ;

#5.7 Base-16 Digit

Base16Digit :
  Digit | 'A' | 'B' | 'C' | 'D' | 'E' | 'F'
  ;

#5.8 Base-2 Digit

Base2Digit :
  '0' | '1'
  ;

#5.9 Digit Separator

DigitSep : "'" ;

#6 String Literal

StringLiteral :
  SingleQuotedString | DoubleQuotedString
  ;

#6.1 Single Quoted String

SingleQuotedString :
  "'" ( QuotableCharacter | '"' )* "'"
  ;

#6.2 Double Quoted String

DoubleQuotedString :
  '"' ( QuotableCharacter | "'" )* '"'
  ;

#6.3 Quotable Character

QuotableCharacter :
  Digit | Letter | Space | NonAlphaNumQuotable | EscapedCharacter
  ;

#6.4 Letter

Letter :
  'A' .. 'Z' | 'a' .. 'z'
  ;

#6.5 Space

Space : ' ' ;

#6.6 Non-Alphanumeric Quotable

NonAlphaNumQuotable :
  '!' | '#' | '$' | '%' | '&' | '(' | ')' | '*' | '+' | ',' |
  '-' | '.' | '/' | ':' | ';' | '<' | '=' | '>' | '?' | '@' |
  '[' | ']' | '^' | '_' | '`' | '{' | '|' | '}' | '~'

#6.7 Escaped Character

EscapedCharacter :
  '\' ( 'n' | 't' | '\' )
  ;

#7 Chevron Text

ChevronText :
  '<<' ( QuotableCharacter | "'" | '"' )* '>>'
  ;