doc: use code markup/markdown in headers

CPP_STYLE_GUIDE.md

@@ -14,9 +14,9 @@ codebase not related to stylistic issues.
   * [Align function arguments vertically](#align-function-arguments-vertically)
   * [Initialization lists](#initialization-lists)
   * [CamelCase for methods, functions, and classes](#camelcase-for-methods-functions-and-classes)
-  * [snake\_case for local variables and parameters](#snake_case-for-local-variables-and-parameters)
-  * [snake\_case\_ for private class fields](#snake_case_-for-private-class-fields)
-  * [snake\_case for C-like structs](#snake_case-for-c-like-structs)
+  * [`snake_case` for local variables and parameters](#snake_case-for-local-variables-and-parameters)
+  * [`snake_case_` for private class fields](#snake_case_-for-private-class-fields)
+  * [`snake_case` for C-like structs](#snake_case-for-c-like-structs)
   * [Space after `template`](#space-after-template)
 * [Memory Management](#memory-management)
   * [Memory allocation](#memory-allocation)
@@ -155,15 +155,15 @@ class FooBar {
 };
 ```
 
-### snake\_case for local variables and parameters
+### `snake_case` for local variables and parameters
 
 ```c++
 int FunctionThatDoesSomething(const char* important_string) {
   const char* pointer_into_string = important_string;
 }
 ```
 
-### snake\_case\_ for private class fields
+### `snake_case_` for private class fields
 
 ```c++
 class Foo {
@@ -172,8 +172,9 @@ class Foo {
 };
 ```
 
-### snake\_case for C-like structs
-For plain C-like structs snake_case can be used.
+### `snake_case` for C-like structs
+
+For `plain C-like structs snake_case can be used.
 
 ```c++
 struct foo_bar {

benchmark/README.md

@@ -74,21 +74,21 @@ The common.js module is used by benchmarks for consistency across repeated
 tasks. It has a number of helpful functions and properties to help with
 writing benchmarks.
 
-### createBenchmark(fn, configs\[, options\])
+### `createBenchmark(fn, configs[, options])`
 
 See [the guide on writing benchmarks](writing-and-running-benchmarks.md#basics-of-a-benchmark).
 
-### default\_http\_benchmarker
+### `default_http_benchmarker`
 
 The default benchmarker used to run HTTP benchmarks.
 See [the guide on writing HTTP benchmarks](writing-and-running-benchmarks.md#creating-an-http-benchmark).
 
-### PORT
+### `PORT`
 
 The default port used to run HTTP benchmarks.
 See [the guide on writing HTTP benchmarks](writing-and-running-benchmarks.md#creating-an-http-benchmark).
 
-### sendResult(data)
+### `sendResult(data)`
 
 Used in special benchmarks that can't use `createBenchmark` and the object
 it returns to accomplish what they need. This function reports timing

doc/api/fs.md

@@ -5093,7 +5093,7 @@ changes:
 
 The `Promise` is resolved with the [`fs.Stats`][] object for the given `path`.
 
-### `fsPromises.symlink(target, path\[, type\])`
+### `fsPromises.symlink(target, path[, type])`
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 added: v10.0.0
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doc/api/http2.md

@@ -3233,7 +3233,7 @@ const server = http2.createServer((req, res) => {
 });
 ```
 
-#### `response.setTimeout(msecs\[, callback\])`
+#### `response.setTimeout(msecs[, callback])`
 <!-- YAML
 added: v8.4.0
 -->