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Documentation change (#3672)

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Co-authored-by: Florian Albrechtskirchinger <falbrechtskirchinger@gmail.com>
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Niels Lohmann
2022-08-05 19:51:39 +02:00
committed by GitHub
co-authored by Florian Albrechtskirchinger
parent 9e1a7c85e3
commit 7b6cf5918b
65 changed files with 582 additions and 302 deletions
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docs/mkdocs/docs/features/parsing/parser_callbacks.md
+12 -8
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@@ -2,9 +2,10 @@
## Overview
With a parser callback function, the result of parsing a JSON text can be influenced. When passed to `parse`, it is called on certain events
(passed as `parse_event_t` via parameter `event`) with a set recursion depth `depth` and context JSON value `parsed`. The return value of the
callback function is a boolean indicating whether the element that emitted the callback shall be kept or not.
With a parser callback function, the result of parsing a JSON text can be influenced. When passed to `parse`, it is
called on certain events (passed as `parse_event_t` via parameter `event`) with a set recursion depth `depth` and
context JSON value `parsed`. The return value of the callback function is a boolean indicating whether the element that
emitted the callback shall be kept or not.
The type of the callback function is:
@@ -17,8 +18,8 @@ using parser_callback_t =
## Callback event types
We distinguish six scenarios (determined by the event type) in which the callback function can be called. The following table describes the values
of the parameters `depth`, `event`, and `parsed`.
We distinguish six scenarios (determined by the event type) in which the callback function can be called. The following
table describes the values of the parameters `depth`, `event`, and `parsed`.
| parameter `event` | description | parameter `depth` | parameter `parsed` |
|-------------------------------|-----------------------------------------------------------|-------------------------------------------|----------------------------------|
@@ -59,10 +60,13 @@ of the parameters `depth`, `event`, and `parsed`.
## Return value
Discarding a value (i.e., returning `#!c false`) has different effects depending on the context in which function was called:
Discarding a value (i.e., returning `#!c false`) has different effects depending on the context in which the function
was called:
- Discarded values in structured types are skipped. That is, the parser will behave as if the discarded value was never read.
- In case a value outside a structured type is skipped, it is replaced with `#!json null`. This case happens if the top-level element is skipped.
- Discarded values in structured types are skipped. That is, the parser will behave as if the discarded value was never
read.
- In case a value outside a structured type is skipped, it is replaced with `#!json null`. This case happens if the
top-level element is skipped.
??? example