Grammar Documentation

abnf_grammar

entry point

Grammar definition

abnf_grammar
    : rule_def* EOF
    ;

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References

rule_def

rule = rulename defined-as elements c-nl

Grammar definition

rule_def
    : rule_name defined_as alternation c_nl
    ;

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Referenced by

abnf_grammar

References

rule_name defined_as alternation c_nl

rule_name

rulename = ALPHA *(ALPHA / DIGIT / "-")

Grammar definition

rule_name
    : RULENAME
    ;

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Referenced by

rule_def element

defined_as

defined-as = *c-wsp ("=" / "=/") *c-wsp

Grammar definition

defined_as
    : EQUALS
    | INCREMENTAL_ALT
    ;

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Referenced by

rule_def

alternation

alternation = concatenation *(*c-wsp "/" *c-wsp concatenation)

Grammar definition

alternation
    : concatenation (SLASH concatenation)*
    ;

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Referenced by

rule_def group option

References

concatenation

concatenation = repetition *(1*c-wsp repetition)

Grammar definition

concatenation
    : repetition+
    ;

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Referenced by

alternation

References

repetition

repetition = [repeat] element

Grammar definition

repetition
    : repeat? element
    ;

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Referenced by

concatenation

References

repeat element

repeat

repeat = 1*DIGIT / (*DIGIT "*" *DIGIT)

Grammar definition

repeat
    : n = DIGIT_VAL ASTERISK m = DIGIT_VAL  // n*m — between n and m
    | n = DIGIT_VAL ASTERISK                // n*  — n or more
    | ASTERISK m = DIGIT_VAL                //  *m — up to m
    | ASTERISK                              //  *  — zero or more
    | n = DIGIT_VAL                         // n   — exactly n
    ;

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Referenced by

repetition

element

element = rulename / group / option / char-val / num-val / prose-val

Grammar definition

element
    : rule_name
    | group
    | option
    | char_val
    | num_val
    | PROSE_VAL
    ;

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Referenced by

repetition

References

rule_name group option char_val num_val

group

group = "(" *c-wsp alternation *c-wsp ")"

Grammar definition

group
    : LPAREN alternation RPAREN
    ;

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Referenced by

element

References

alternation

option

option = "[" *c-wsp alternation *c-wsp "]"

Grammar definition

option
    : LBRACKET alternation RBRACKET
    ;

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Referenced by

element

References

alternation

char_val

char-val = case-insensitive-string / case-sensitive-string case-insensitive-string = [ "%i" ] quoted-string case-sensitive-string = "%s" quoted-string (RFC 7405)

Grammar definition

char_val
    : CASE_SENSITIVE_STRING
    | CASE_INSENSITIVE_STRING
    | QUOTED_STRING
    ;

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Referenced by

element

num_val

num-val = "%" (bin-val / dec-val / hex-val)

Grammar definition

num_val
    : BIN_VAL
    | DEC_VAL
    | HEX_VAL
    ;

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Referenced by

element

c_nl

c-nl = comment / CRLF / LF

Grammar definition

c_nl
    : CRLF
    | LF
    | EOF
    ;

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Referenced by

rule_def