Passa al contenuto principale

Appendix A. Collected ABNF Grammars (Grammatiche ABNF raccolte)

Appendix A. Collected ABNF Grammars (Grammatiche ABNF raccolte)

Questa appendice raccoglie la grammatica ABNF dai passaggi ABNF usati in tutto il documento.

La Figura 2 contiene la grammatica ABNF raccolta che definisce la sintassi di un'interrogazione JSONPath.

jsonpath-query      = root-identifier segments
segments = *(S segment)
B                   = %x20 /    ; Space
%x09 / ; Horizontal tab
%x0A / ; Line feed or New line
%x0D ; Carriage return
S = *B ; optional blank space
root-identifier = "$"
selector = name-selector /
wildcard-selector /
slice-selector /
index-selector /
filter-selector
name-selector = string-literal
string-literal      = %x22 *double-quoted %x22 /     ; "string"
%x27 *single-quoted %x27 ; 'string'
double-quoted       = unescaped /
%x27 / ; '
ESC %x22 / ; \"
ESC escapable
single-quoted       = unescaped /
%x22 / ; "
ESC %x27 / ; \'
ESC escapable
ESC                 = %x5C                           ; \ backslash
unescaped           = %x20-21 /                      ; see RFC 8259
; omit 0x22 "
%x23-26 /
; omit 0x27 '
%x28-5B /
; omit 0x5C \
%x5D-D7FF /
; skip surrogate code points
%xE000-10FFFF
escapable           = %x62 / ; b BS backspace U+0008
%x66 / ; f FF form feed U+000C
%x6E / ; n LF line feed U+000A
%x72 / ; r CR carriage return U+000D
%x74 / ; t HT horizontal tab U+0009
"/" / ; / slash (solidus) U+002F
"\" / ; \ backslash (reverse solidus) U+005C
(%x75 hexchar) ; uXXXX U+XXXX
hexchar             = non-surrogate /
(high-surrogate "\" %x75 low-surrogate)
non-surrogate = ((DIGIT / "A"/"B"/"C" / "E"/"F") 3HEXDIG) /
("D" %x30-37 2HEXDIG )
high-surrogate = "D" ("8"/"9"/"A"/"B") 2HEXDIG
low-surrogate = "D" ("C"/"D"/"E"/"F") 2HEXDIG
HEXDIG              = DIGIT / "A" / "B" / "C" / "D" / "E" / "F"
wildcard-selector = "*"
index-selector = int ; decimal integer
int                 = "0" /
(["-"] DIGIT1 *DIGIT) ; - optional
DIGIT1 = %x31-39 ; 1-9 non-zero digit
slice-selector = [start S] ":" S [end S] [":" [S step ]]

start = int ; included in selection end = int ; not included in selection step = int ; default: 1 filter-selector = "?" S logical-expr logical-expr = logical-or-expr logical-or-expr = logical-and-expr *(S "||" S logical-and-expr) ; disjunction ; binds less tightly than conjunction logical-and-expr = basic-expr *(S "&&" S basic-expr) ; conjunction ; binds more tightly than disjunction

basic-expr          = paren-expr /
comparison-expr /
test-expr
paren-expr          = [logical-not-op S] "(" S logical-expr S ")"
; parenthesized expression
logical-not-op = "!" ; logical NOT operator
test-expr = [logical-not-op S]
(filter-query / ; existence/non-existence
function-expr) ; LogicalType or NodesType
filter-query = rel-query / jsonpath-query
rel-query = current-node-identifier segments
current-node-identifier = "@"
comparison-expr = comparable S comparison-op S comparable
literal = number / string-literal /
true / false / null
comparable = literal /
singular-query / ; singular query value
function-expr ; ValueType
comparison-op = "==" / "!=" /
"<=" / ">=" /
"<" / ">"
singular-query      = rel-singular-query / abs-singular-query
rel-singular-query = current-node-identifier singular-query-segments
abs-singular-query = root-identifier singular-query-segments
singular-query-segments = *(S (name-segment / index-segment))
name-segment = ("[" name-selector "]") /
("." member-name-shorthand)
index-segment = "[" index-selector "]"
number = (int / "-0") [ frac ] [ exp ] ; decimal number
frac = "." 1*DIGIT ; decimal fraction
exp = "e" [ "-" / "+" ] 1*DIGIT ; decimal exponent
true = %x74.72.75.65 ; true
false = %x66.61.6c.73.65 ; false
null = %x6e.75.6c.6c ; null
function-name = function-name-first *function-name-char
function-name-first = LCALPHA
function-name-char = function-name-first / "_" / DIGIT
LCALPHA = %x61-7A ; "a".."z"
function-expr       = function-name "(" S [function-argument
*(S "," S function-argument)] S ")"
function-argument = literal /
filter-query / ; (includes singular-query)
logical-expr /
function-expr
segment = child-segment / descendant-segment
child-segment = bracketed-selection /
("."
(wildcard-selector /
member-name-shorthand))

bracketed-selection = "[" S selector *(S "," S selector) S "]"

member-name-shorthand = name-first *name-char
name-first = ALPHA /
"_" /
%x80-D7FF /
; skip surrogate code points
%xE000-10FFFF
name-char = name-first / DIGIT
DIGIT               = %x30-39              ; 0-9
ALPHA = %x41-5A / %x61-7A ; A-Z / a-z
descendant-segment = ".." (bracketed-selection /
wildcard-selector /
member-name-shorthand)

Figura 2: ABNF raccolta delle interrogazioni JSONPath

La Figura 3 contiene la grammatica ABNF raccolta che definisce la sintassi di un Normalized Path JSONPath usando anche le regole root-identifier, ESC, DIGIT, e DIGIT1 dalla Figura 2.

normalized-path      = root-identifier *(normal-index-segment)
normal-index-segment = "[" normal-selector "]"
normal-selector = normal-name-selector / normal-index-selector
normal-name-selector = %x27 *normal-single-quoted %x27 ; 'string'
normal-single-quoted = normal-unescaped /
ESC normal-escapable
normal-unescaped = ; omit %x0-1F control codes
%x20-26 /
; omit 0x27 '
%x28-5B /
; omit 0x5C \
%x5D-D7FF /
; skip surrogate code points
%xE000-10FFFF
normal-escapable     = %x62 / ; b BS backspace U+0008
%x66 / ; f FF form feed U+000C
%x6E / ; n LF line feed U+000A
%x72 / ; r CR carriage return U+000D
%x74 / ; t HT horizontal tab U+0009
"'" / ; ' apostrophe U+0027
"\" / ; \ backslash (reverse solidus) U+005C
(%x75 normal-hexchar)
; certain values u00xx U+00XX
normal-hexchar = "0" "0"
(
("0" %x30-37) / ; "00"-"07"
; omit U+0008-U+000A BS HT LF
("0" %x62) / ; "0b"
; omit U+000C-U+000D FF CR
("0" %x65-66) / ; "0e"-"0f"
("1" normal-HEXDIG)
)
normal-HEXDIG = DIGIT / %x61-66 ; "0"-"9", "a"-"f"
normal-index-selector = "0" / (DIGIT1 *DIGIT)
; non-negative decimal integer

Figura 3: ABNF raccolta dei Normalized Path JSONPath