Prefer content for page component content

Rather than `html_content`.

devel/manual/fmt.md

@@ -14,7 +14,7 @@ nonnegative integer. The languages defined so far are:
 
 The `Ftext` class can convert between some formats.
 
-(Note that open-source HotCRP ships without Markdown support.)
+(Open-source HotCRP ships without Markdown support.)
 
 
 ## Ftext
@@ -297,7 +297,7 @@ HotCRP understands the following format specifications.
 | Format specification      | Result                                               |
 |:--------------------------|:-----------------------------------------------------|
 | `:url`                    | The string argument is urlencoded.                   |
-| `:html`                   | The string argument is HTML-encoded; i.e., `&<>"'` are replaced by HTML entities. |
+| `:html`                   | The string argument is HTML-encoded: `&<>"'` are replaced by HTML entities. |
 | `:ftext`                  | When possible, the string argument is incorporated as an ftext, rather than having its format translated or stripped. |
 | `:humanize_url`           | If the argument string is a simple url, such as `https://hotcrp.com/privacy`, it is replaced by a shorter version, such as `hotcrp.com/privacy`. |
 | `:.2f`, etc.              | The numeric argument is rendered using a printf-style specification. |

devel/manual/pages.md

@@ -59,26 +59,34 @@ and terminates request processing. A `request_function` may also throw a value
 of type `Redirection` to force HotCRP to redirect the user’s browser to
 another URI.
 
-## Rendering the result
+## Printing the result
 
 Assuming the `request_function`s do not throw a redirection, HotCRP next
 re-scans the component list and prints the corresponding components.
 
-To print a component, HotCRP checks for:
+Many HotCRP pages do not have separate `request_function`s, instead handling
+all request parsing as part of the first `print_function` for a page.
 
-1. A `print_function` property. If present, this calls the corresponding PHP
-   callback, using the same syntax and arguments as `request_function`, above.
+To print a component, HotCRP:
 
-2. Otherwise, an `html_content` property. If present, this is copied to the output.
+1. First, HotCRP prints the component itself, by looking for a
+   `print_function` or `content` property.
 
-3. In either case, if the component has a `print_members` property, HotCRP
-   next prints the members of the group with the component’s name.
+    * If `print_function` is present, HotCRP calls the corresponding PHP
+      callback to print the component. The `print_function` property uses the
+      same syntax as `request_function`, and the callback takes the same
+      arguments.
 
-A `print_function` may cancel further rendering by returning explicit `false`,
-or by throwing a `Redirection` or `PageCompletion` exception.
+      A `print_function` may cancel further rendering by returning explicit
+      `false`, or by throwing a `Redirection` or `PageCompletion` exception.
 
-Many HotCRP pages do not have separate `request_function`s, instead handling
-all request parsing as part of the first `print_function` for a page.
+    * Otherwise, if `content` is present, HotCRP prints that content. This
+      property is an [ftext string][ftext].
+
+    * Otherwise, HotCRP prints nothing for the component itself.
+
+2. Second, if the component has a `print_members` property, HotCRP recursively
+   prints the members of the group with the component’s name.
 
 ## Shorthand
 
@@ -108,3 +116,4 @@ components support conditions relating to the current request.
 
 
 [components]: ./components.md
+[ftext]: ./fmt.md

src/componentset.php

@@ -518,8 +518,10 @@ private function _print_body($gj, $print_members) {
         $result = null;
         if (isset($gj->print_function)) {
             $result = $this->call_function($gj, $gj->print_function, $gj);
+        } else if (isset($gj->content)) {
+            echo Ftext::as(5, $gj->content, 0);
         } else if (isset($gj->html_content)) {
-            echo $gj->html_content;
+            echo $gj->html_content; /* XXX backward compat */
         }
         if (isset($gj->print_members)) {
             $print_members = $gj->print_members;