diff options
Diffstat (limited to '')
| -rw-r--r-- | src/construct/partial_label.rs | 81 |
1 files changed, 75 insertions, 6 deletions
diff --git a/src/construct/partial_label.rs b/src/construct/partial_label.rs index c772c56..f7ce8d7 100644 --- a/src/construct/partial_label.rs +++ b/src/construct/partial_label.rs @@ -1,9 +1,65 @@ +//! Label occurs in [definition][] and label end. +//! +//! They’re formed with the following BNF: +//! +//! ```bnf +//! ; Restriction: maximum `999` codes allowed between brackets. +//! ; Restriction: no blank lines. +//! ; Restriction: at least 1 non-space and non-eol code must exist. +//! label ::= '[' *( label_text | label_escape ) ']' +//! label_text ::= code - '[' - '\\' - ']' +//! label_escape ::= '\\' [ '[' | '\\' | ']' ] +//! ``` +//! +//! The maximum allowed size of the label, without the brackets, is `999` +//! (inclusive), which is defined in +//! [`LINK_REFERENCE_SIZE_MAX`][link_reference_size_max]. +//! +//! Labels can contain line endings and whitespace, but they are not allowed to +//! contain blank lines, and they must not be blank themselves. +//! +//! The label is interpreted as the [string][] content type. +//! That means that character escapes and character reference are allowed. +//! +//! > 👉 **Note**: this label relates to, but is not, the initial “label” of +//! > what is know as a reference in markdown: +//! > +//! > | Kind | Link | Image | +//! > | --------- | -------- | --------- | +//! > | Shortcut | `[x]` | `![x]` | +//! > | Collapsed | `[x][]` | `![x][]` | +//! > | Full | `[x][y]` | `![x][y]` | +//! > +//! > The 6 above things are references, in the three kinds they come in, as +//! > links and images. +//! > The label that this module focusses on is only the thing that contains +//! > `y`. +//! > +//! > The thing that contains `x` is not a single thing when parsing markdown, +//! > but instead constists of an opening (label start (image) or label start +//! > (link)) and a closing (label end), so as to allow further phrasing such +//! > as code (text) or attention. +//! +//! ## References +//! +//! * [`micromark-factory-label/index.js` in `micromark`](https://github.com/micromark/micromark/blob/main/packages/micromark-factory-label/dev/index.js) +//! +//! [definition]: crate::construct::definition +//! [string]: crate::content::string +//! [link_reference_size_max]: crate::constant::LINK_REFERENCE_SIZE_MAX +//! +//! <!-- To do: link label end, label starts. --> + // To do: pass token types in. use crate::constant::LINK_REFERENCE_SIZE_MAX; use crate::tokenizer::{Code, State, StateFnResult, TokenType, Tokenizer}; -/// To do. +/// Before a label. +/// +/// ```markdown +/// |[a] +/// ``` pub fn start(tokenizer: &mut Tokenizer, code: Code) -> StateFnResult { match code { Code::Char('[') => { @@ -14,12 +70,16 @@ pub fn start(tokenizer: &mut Tokenizer, code: Code) -> StateFnResult { tokenizer.enter(TokenType::DefinitionLabelData); (State::Fn(Box::new(|t, c| at_break(t, c, false, 0))), None) } - // To do: allow? - _ => unreachable!("expected `[` at start of label"), + _ => (State::Nok, None), } } -/// To do. +/// In a label, at something. +/// +/// ```markdown +/// [|a] +/// [a|] +/// ``` fn at_break(tokenizer: &mut Tokenizer, code: Code, data: bool, size: usize) -> StateFnResult { match code { Code::None | Code::Char('[') => (State::Nok, None), @@ -37,6 +97,7 @@ fn at_break(tokenizer: &mut Tokenizer, code: Code, data: bool, size: usize) -> S tokenizer.enter(TokenType::LineEnding); tokenizer.consume(code); tokenizer.exit(TokenType::LineEnding); + // To do: limit blank lines. ( State::Fn(Box::new(move |t, c| at_break(t, c, data, size))), None, @@ -50,7 +111,11 @@ fn at_break(tokenizer: &mut Tokenizer, code: Code, data: bool, size: usize) -> S } } -/// To do. +/// In a label, in text. +/// +/// ```markdown +/// [a|b] +/// ``` fn label(tokenizer: &mut Tokenizer, code: Code, data: bool, size: usize) -> StateFnResult { match code { Code::None | Code::CarriageReturnLineFeed | Code::Char('\r' | '\n' | '[' | ']') => { @@ -85,7 +150,11 @@ fn label(tokenizer: &mut Tokenizer, code: Code, data: bool, size: usize) -> Stat } } -/// To do. +/// After `\` in a label. +/// +/// ```markdown +/// [a\|[b] +/// ``` fn escape(tokenizer: &mut Tokenizer, code: Code, data: bool, size: usize) -> StateFnResult { match code { Code::Char('[' | '\\' | ']') => { |