Help: Revise docs on Scripting Commands

Revise docs for all "Scripting Commands", except four find_XXX
that use a macro suite of their own.

* Take full advantage of the improved syntax highlighting.
* Make consequential use of <..> placeholders.
* Clarify things here and there in the text.

Specific improvements to some command docs:

* "math": Correct description of novel hexadecimal capability.
* "if", "foreach", "while": Provide link to "endif" etc
* "foreach", "while": Mention "break" and "continue".
* "foreach": Simplify explanation of ``RANGE`` and ``IN`` signatures;
   advise against negative arguments or reverse ranges (compare issue #18461)
* "endif", "endfunction" etc: Explain that the argument is optional and
   maintained for compatibility only

1 files changed, 7 insertions, 8 deletions

diff --git a/Help/command/option.rst b/Help/command/option.rst
index 4fabb87..8956307 100644
--- a/Help/command/option.rst
+++ b/Help/command/option.rst
@@ -1,17 +1,16 @@
 option
 ------
 
-Provides an option that the user can optionally select.
+Provide an option that the user can optionally select.
 
-::
+.. code-block:: cmake
 
-  option(<option_variable> "help string describing option"
-         [initial value])
+  option(<variable> "<help_text>" [value])
 
-Provide an option for the user to select as ``ON`` or ``OFF``.  If no
-initial value is provided, ``OFF`` is used.  If the option is already
-set as a normal variable then the command does nothing
-(see policy :policy:`CMP0077`).
+Provides an option for the user to select as ``ON`` or ``OFF``.
+If no initial ``<value>`` is provided, ``OFF`` is used.
+If ``<variable>`` is already set as a normal variable
+then the command does nothing (see policy :policy:`CMP0077`).
 
 If you have options that depend on the values of other options, see
 the module help for :module:`CMakeDependentOption`.