Docs: Improve grammar in some DocBlocks for more clarity and consistency.

Follow-up to [8215], [8598].

Props prab18hat, dhruvang21, swissspidy, SergeyBiryukov.
Fixes #63892.

git-svn-id: https://develop.svn.wordpress.org/trunk@60687 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-includes/functions.php

@@ -760,17 +760,17 @@ function is_serialized_string( $data ) {
 }
 
 /**
- * Retrieves post title from XMLRPC XML.
+ * Retrieves post title from XML-RPC XML.
  *
- * If the title element is not part of the XML, then the default post title from
- * the $post_default_title will be used instead.
+ * If the `title` element is not found in the XML, the default post title
+ * from the `$post_default_title` global will be used instead.
  *
  * @since 0.71
  *
  * @global string $post_default_title Default XML-RPC post title.
  *
- * @param string $content XMLRPC XML Request content
- * @return string Post title
+ * @param string $content XML-RPC XML Request content.
+ * @return string Post title.
  */
 function xmlrpc_getposttitle( $content ) {
 	global $post_default_title;
@@ -783,18 +783,20 @@ function xmlrpc_getposttitle( $content ) {
 }
 
 /**
- * Retrieves the post category or categories from XMLRPC XML.
+ * Retrieves the post category or categories from XML-RPC XML.
+ *
+ * If the `category` element is not found in the XML, the default post category
+ * from the `$post_default_category` global will be used instead.
+ * The return type will then be a string.
  *
- * If the category element is not found, then the default post category will be
- * used. The return type then would be what $post_default_category. If the
- * category is found, then it will always be an array.
+ * If the `category` element is found, the return type will be an array.
  *
  * @since 0.71
  *
  * @global string $post_default_category Default XML-RPC post category.
  *
- * @param string $content XMLRPC XML Request content
- * @return string|array List of categories or category name.
+ * @param string $content XML-RPC XML Request content.
+ * @return string[]|string An array of category names or default category name.
  */
 function xmlrpc_getpostcategory( $content ) {
 	global $post_default_category;
@@ -808,12 +810,12 @@ function xmlrpc_getpostcategory( $content ) {
 }
 
 /**
- * XMLRPC XML content without title and category elements.
+ * XML-RPC XML content without title and category elements.
  *
  * @since 0.71
  *
  * @param string $content XML-RPC XML Request content.
- * @return string XMLRPC XML Request content without title and category elements.
+ * @return string XML-RPC XML Request content without title and category elements.
  */
 function xmlrpc_removepostdata( $content ) {
 	$content = preg_replace( '/<title>(.+?)<\/title>/si', '', $content );
@@ -1024,10 +1026,10 @@ function is_new_day() {
 }
 
 /**
- * Builds URL query based on an associative and, or indexed array.
+ * Builds a URL query based on an associative or indexed array.
  *
- * This is a convenient function for easily building url queries. It sets the
- * separator to '&' and uses _http_build_query() function.
+ * This is a convenient function for easily building URL queries.
+ * It sets the separator to '&' and uses the _http_build_query() function.
  *
  * @since 2.3.0
  *
@@ -4166,7 +4168,7 @@ function _jsonp_wp_die_handler( $message, $title = '', $args = array() ) {
 /**
  * Kills WordPress execution and displays XML response with an error message.
  *
- * This is the handler for wp_die() when processing XMLRPC requests.
+ * This is the handler for wp_die() when processing XML-RPC requests.
  *
  * @since 3.2.0
  * @access private