leo/grammar/format-abnf-grammar.txt

; Copyright (C) 2019-2021 Aleo Systems Inc.
; This file is part of the Leo library.

; The Leo library is free software: you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, either version 3 of the License, or
; (at your option) any later version.

; The Leo library is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.

; You should have received a copy of the GNU General Public License
; along with the Leo library. If not, see <https://www.gnu.org/licenses/>.

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; Background on ABNF
; ------------------

; ABNF is an Internet standard:
; for more info please checkout the
; [README](./README.md) in this directory.

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; Format String
; -------------------

; This ABNF grammar consists of one grammar:
; that describes how a Leo string-literal is parsed
; for formatting.  Meaning in this context
; all characters are already parsed and we don't
; have to worry about escapes or etc.

not-brace = %x0-7A / %x7C / %x7E-10FFFF ; anything but { or }

format-string-container = "{}"

format-string-open-brace = "{{"

format-string-close-brace = "}}"

format-string-element = not-brace
                        / format-string-container
                        / format-string-open-brace
                        / format-string-close-brace
		      
format-string = *format-string-element