podman

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;; This document describes TOML's syntax, using the ABNF format (defined in
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;; RFC 5234 -- https://www.ietf.org/rfc/rfc5234.txt).
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;;
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;; All valid TOML documents will match this description, however certain
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;; invalid documents would need to be rejected as per the semantics described
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;; in the supporting text description.
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;; It is possible to try this grammar interactively, using instaparse.
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;;     http://instaparse.mojombo.com/
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;;
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;; To do so, in the lower right, click on Options and change `:input-format` to
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;; ':abnf'. Then paste this entire ABNF document into the grammar entry box
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;; (above the options). Then you can type or paste a sample TOML document into
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;; the beige box on the left. Tada!
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;; Overall Structure
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toml = expression *( newline expression )
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expression =  ws [ comment ]
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expression =/ ws keyval ws [ comment ]
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expression =/ ws table ws [ comment ]
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;; Whitespace
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ws = *wschar
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wschar =  %x20  ; Space
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wschar =/ %x09  ; Horizontal tab
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;; Newline
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newline =  %x0A     ; LF
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newline =/ %x0D.0A  ; CRLF
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;; Comment
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comment-start-symbol = %x23 ; #
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non-ascii = %x80-D7FF / %xE000-10FFFF
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non-eol = %x09 / %x20-7F / non-ascii
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comment = comment-start-symbol *non-eol
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;; Key-Value pairs
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keyval = key keyval-sep val
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key = simple-key / dotted-key
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simple-key = quoted-key / unquoted-key
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unquoted-key = 1*( ALPHA / DIGIT / %x2D / %x5F ) ; A-Z / a-z / 0-9 / - / _
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quoted-key = basic-string / literal-string
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dotted-key = simple-key 1*( dot-sep simple-key )
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dot-sep   = ws %x2E ws  ; . Period
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keyval-sep = ws %x3D ws ; =
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val = string / boolean / array / inline-table / date-time / float / integer
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;; String
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string = ml-basic-string / basic-string / ml-literal-string / literal-string
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;; Basic String
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basic-string = quotation-mark *basic-char quotation-mark
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quotation-mark = %x22            ; "
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basic-char = basic-unescaped / escaped
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basic-unescaped = wschar / %x21 / %x23-5B / %x5D-7E / non-ascii
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escaped = escape escape-seq-char
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escape = %x5C                   ; \
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escape-seq-char =  %x22         ; "    quotation mark  U+0022
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escape-seq-char =/ %x5C         ; \    reverse solidus U+005C
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escape-seq-char =/ %x62         ; b    backspace       U+0008
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escape-seq-char =/ %x66         ; f    form feed       U+000C
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escape-seq-char =/ %x6E         ; n    line feed       U+000A
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escape-seq-char =/ %x72         ; r    carriage return U+000D
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escape-seq-char =/ %x74         ; t    tab             U+0009
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escape-seq-char =/ %x75 4HEXDIG ; uXXXX                U+XXXX
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escape-seq-char =/ %x55 8HEXDIG ; UXXXXXXXX            U+XXXXXXXX
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;; Multiline Basic String
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ml-basic-string = ml-basic-string-delim [ newline ] ml-basic-body
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                  ml-basic-string-delim
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ml-basic-string-delim = 3quotation-mark
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ml-basic-body = *mlb-content *( mlb-quotes 1*mlb-content ) [ mlb-quotes ]
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mlb-content = mlb-char / newline / mlb-escaped-nl
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mlb-char = mlb-unescaped / escaped
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mlb-quotes = 1*2quotation-mark
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mlb-unescaped = wschar / %x21 / %x23-5B / %x5D-7E / non-ascii
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mlb-escaped-nl = escape ws newline *( wschar / newline )
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;; Literal String
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literal-string = apostrophe *literal-char apostrophe
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apostrophe = %x27 ; ' apostrophe
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literal-char = %x09 / %x20-26 / %x28-7E / non-ascii
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;; Multiline Literal String
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ml-literal-string = ml-literal-string-delim [ newline ] ml-literal-body
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                    ml-literal-string-delim
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ml-literal-string-delim = 3apostrophe
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ml-literal-body = *mll-content *( mll-quotes 1*mll-content ) [ mll-quotes ]
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mll-content = mll-char / newline
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mll-char = %x09 / %x20-26 / %x28-7E / non-ascii
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mll-quotes = 1*2apostrophe
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;; Integer
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integer = dec-int / hex-int / oct-int / bin-int
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minus = %x2D                       ; -
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plus = %x2B                        ; +
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underscore = %x5F                  ; _
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digit1-9 = %x31-39                 ; 1-9
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digit0-7 = %x30-37                 ; 0-7
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digit0-1 = %x30-31                 ; 0-1
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hex-prefix = %x30.78               ; 0x
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oct-prefix = %x30.6F               ; 0o
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bin-prefix = %x30.62               ; 0b
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dec-int = [ minus / plus ] unsigned-dec-int
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unsigned-dec-int = DIGIT / digit1-9 1*( DIGIT / underscore DIGIT )
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hex-int = hex-prefix HEXDIG *( HEXDIG / underscore HEXDIG )
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oct-int = oct-prefix digit0-7 *( digit0-7 / underscore digit0-7 )
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bin-int = bin-prefix digit0-1 *( digit0-1 / underscore digit0-1 )
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;; Float
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float = float-int-part ( exp / frac [ exp ] )
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float =/ special-float
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float-int-part = dec-int
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frac = decimal-point zero-prefixable-int
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decimal-point = %x2E               ; .
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zero-prefixable-int = DIGIT *( DIGIT / underscore DIGIT )
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exp = "e" float-exp-part
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float-exp-part = [ minus / plus ] zero-prefixable-int
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special-float = [ minus / plus ] ( inf / nan )
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inf = %x69.6e.66  ; inf
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nan = %x6e.61.6e  ; nan
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;; Boolean
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boolean = true / false
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true    = %x74.72.75.65     ; true
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false   = %x66.61.6C.73.65  ; false
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;; Date and Time (as defined in RFC 3339)
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date-time      = offset-date-time / local-date-time / local-date / local-time
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date-fullyear  = 4DIGIT
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date-month     = 2DIGIT  ; 01-12
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date-mday      = 2DIGIT  ; 01-28, 01-29, 01-30, 01-31 based on month/year
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time-delim     = "T" / %x20 ; T, t, or space
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time-hour      = 2DIGIT  ; 00-23
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time-minute    = 2DIGIT  ; 00-59
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time-second    = 2DIGIT  ; 00-58, 00-59, 00-60 based on leap second rules
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time-secfrac   = "." 1*DIGIT
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time-numoffset = ( "+" / "-" ) time-hour ":" time-minute
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time-offset    = "Z" / time-numoffset
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partial-time   = time-hour ":" time-minute ":" time-second [ time-secfrac ]
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full-date      = date-fullyear "-" date-month "-" date-mday
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full-time      = partial-time time-offset
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;; Offset Date-Time
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offset-date-time = full-date time-delim full-time
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;; Local Date-Time
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local-date-time = full-date time-delim partial-time
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;; Local Date
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local-date = full-date
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;; Local Time
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local-time = partial-time
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;; Array
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array = array-open [ array-values ] ws-comment-newline array-close
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array-open =  %x5B ; [
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array-close = %x5D ; ]
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array-values =  ws-comment-newline val ws-comment-newline array-sep array-values
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array-values =/ ws-comment-newline val ws-comment-newline [ array-sep ]
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array-sep = %x2C  ; , Comma
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ws-comment-newline = *( wschar / [ comment ] newline )
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;; Table
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table = std-table / array-table
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;; Standard Table
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std-table = std-table-open key std-table-close
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std-table-open  = %x5B ws     ; [ Left square bracket
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std-table-close = ws %x5D     ; ] Right square bracket
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;; Inline Table
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inline-table = inline-table-open [ inline-table-keyvals ] inline-table-close
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inline-table-open  = %x7B ws     ; {
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inline-table-close = ws %x7D     ; }
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inline-table-sep   = ws %x2C ws  ; , Comma
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inline-table-keyvals = keyval [ inline-table-sep inline-table-keyvals ]
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;; Array Table
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array-table = array-table-open key array-table-close
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array-table-open  = %x5B.5B ws  ; [[ Double left square bracket
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array-table-close = ws %x5D.5D  ; ]] Double right square bracket
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;; Built-in ABNF terms, reproduced here for clarity
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ALPHA = %x41-5A / %x61-7A ; A-Z / a-z
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DIGIT = %x30-39 ; 0-9
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HEXDIG = DIGIT / "A" / "B" / "C" / "D" / "E" / "F"
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