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150 lines
8.1 KiB
Markdown
150 lines
8.1 KiB
Markdown
# Event System
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## Introduction
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## The Event Object
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## Events
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Events are raised when a subparser is run (or about to be run).
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Within a subparser, the events always follow a certain order (sequence). For instance, **.before** events always run before **.captureStart**.
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Each subparser raises several events sequentially:
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1. **.start**: **always runs** except it subparser is disabled
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Raised when the **subparser has started**, but no capturing or any modification to the text was done.
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**Always runs** (except if the subparser is deactivated through options).
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***Properties***:
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| property | type | access | description |
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|----------|-----------|------------|--------------------------------------------------------------------|
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| input | string | read | The full text that was passed to the subparser |
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| output | string | write | The full text with modification that will be passed along the chain|
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| regex | null | | |
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| matches | null | | |
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Usually you would want to use this event if you wish to change the input to the subparser
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2. **.captureStart**: *might not be run*;
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Raised when a regex match is found and a capture was successful. Some normalization and modification
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of the regex captured groups might be performed.
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Might not be run if no regex match is found.
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***Properties***:
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| property | type | access | description |
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|----------|-----------|------------|--------------------------------------------------------------------|
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| input | string | read | The captured text |
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| output | string | write | The text that will be passed to the subparser/other listeners |
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| regex | RegExp | readonly | Regular Expression used to capture groups |
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| matches | object | read/write | Matches groups. Changes to this object are reflected in the output |
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Usually you would want to use this event if you wish to modify a certain subparser behavior.
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Exs: remove all title attributes from links; change indentation of code blocks; etc...
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3. **.captureEnd**: *might not be run*;
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Raised after the modifications to the captured text are done but before the replacement is introduced in the document.
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Might not be run if no regex match is found.
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***Properties***:
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| property | type | access | description |
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|------------|-----------|------------|--------------------------------------------------------------------------------|
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| input | string | read | The captured text |
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| output | string | write | The text that will be passed to the subparser/other listeners |
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| regex | RegExp | readonly | Regular Expression used to capture groups |
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| matches | object | read/write | Keypairs of matches groups. Changes to this object are reflected in the output |
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| attributes | object | read/write | Attributes to add to the HTML output |
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4. **.beforeHash**: *might not be run*;
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Raised before the output is hashed.
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Always run (except if the subparser was deactivated through options), even if no hashing is performed.
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***Properties***:
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| property | type | access | description |
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|----------|------------|------------|--------------------------------------------------------------------|
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| input | string | read | The captured text |
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| output | string | write | The text that will be passed to the subparser/other listeners |
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| regex | null | | |
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| matches | null | | |
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Usually you would want to use this event if you wish change the subparser output before it is hashed
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5. **.end**: *always runs*;
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Raised when the subparser has finished its work and is about to exit.
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Always runs (except if the subparser is deactivated through options).
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***Properties***:
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| property | type | access | description |
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|----------|-----------|------------|--------------------------------------------------------------------|
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| input | string | read | The partial/full text with the subparser modifications |
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| output | string | write | The text that will be passed to other subparsers |
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| regex | null | | |
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| matches | null | | |
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Usually you would want to use this event if you wish change the subparser hashed output
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### Special Events
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There are some special events that are useful for *"positioning"* a listener extension in the main chain of events.
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Usually these extensions introduce new syntax that, due to precedence
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These events are always guaranteed to be called, regardless of options or circumstances.
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1. **.before_{subparserName}**: *always runs*
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Raised just before the **{subparserName} is about to be entered**.
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***Properties***:
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| property | type | access | description |
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|----------|-----------|------------|--------------------------------------------------------------------|
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| input | string | read | The full text that was passed to the subparser |
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| output | string | write | The full text with modification that will be passed along the chain|
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| regex | null | | |
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| matches | null | | |
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2. **.after**.{subparserName}: *always runs*;
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Raised when the **{subparserName} has exited** and before the next one is called.
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***Properties***:
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| property | type | access | description |
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|----------|-----------|------------|--------------------------------------------------------------------|
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| input | string | read | The partial/full text with the subparser modifications |
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| output | string | write | The text that will be passed to other subparsers |
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| regex | null | | |
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| matches | null | | |
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### Notes
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- There are 2 main differences between **before.{subparserName}** and **{subparserName}.start**.
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1. **before.{subparserName}** is always guaranteed to be called, even if the subparser is disabled,
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while **{subparserName}.start** doesn't.
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ex: `makehtml.before.strikethrough` is always called even if the option `strikethrough` is false
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2. **before.{subparserName}** is only raised once in a span context while **{subparserName}.start** is raised
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everytime **{subparserName}** is called.
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As a rule of thumb,
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## Events List
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