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56c1ef2679
Use an external file to demonstrate the `autoref` role (the external file lets us `literalinclude` and `include` without writing out the source twice, while still showing all the different ways of using our custom roles).
709 lines
30 KiB
ReStructuredText
709 lines
30 KiB
ReStructuredText
Generated help messages and documentation
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=========================================
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All Yosys commands and built-in cell types should include help text, documenting
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their functionality for users. This help text is made available through the
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`help` command, and online via `ReadtheDocs`_ as part of the :doc:`/cmd_ref` and
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:doc:`/cell_index` documentation. When running locally, any commands provided
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by loaded plugins (either from the command line when calling ``yosys``, or
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dynamically with the `plugin` command) will also be available to the `help`
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command.
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.. _ReadtheDocs: https://about.readthedocs.com/
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.. note::
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Since help text for commands is generated from compiled code, the online help
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may differ from that produced by `help`. Some commands, like `abc`, may be
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completely unavailable depending on compile flags; while others may limit
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specific features, such as whether the `synth` script pass uses ABC.
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Command help
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------------
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The first stop for command help text is the ``Pass::short_help``. This is a
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short sentence describing the pass, and is set in the ``Pass`` constructor with
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the name of the pass, as demonstrated here with `chformal`.
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.. literalinclude:: /generated/chformal.cc
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:language: c++
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:start-at: public Pass {
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:end-at: ChformalPass()
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:caption: ``ChformalPass()`` from :file:`passes/cmds/chformal.cc`
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:append:
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// ...
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} ChformalPass;
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All currently available commands are listed with their ``short_help`` string
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when calling `help` without arguments, and is more or less the same as the
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unlisted :ref:`command index <commandindex>`. The string is also used when
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hovering over links to commands in the documentation, and in section headings
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like :ref:`chformal autocmd`.
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The next section shows the complete help text for the `chformal` command. This
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can be displayed locally by using `help <command>` (or ``yosys -h <command>``
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from the command line). The general format is to show each usage signature (how
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the command is called), followed by a paragraph describing what the pass does,
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and a list of options or flags available. Additional arguments in the signature
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or option may use square brackets (``[]``) to indicate optional parts, and angle
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brackets (``<>``) for required parts. The pipe character (``|``) may be used to
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indicate mutually exclusive arguments.
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.. note::
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Remember that when using ``Frontend`` and ``Backend`` the pass name will be
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be prefixed with ``read_`` or ``write_`` respectively. Usage signatures must
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match the pass name available in commands/scripts, which is available as
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``Pass::pass_name``.
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.. todo:: decide on a formatting style for pass options
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.. _chformal autocmd:
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.. autocmd:: chformal
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:noindex:
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Warning flags
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~~~~~~~~~~~~~
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In order to support commands which are not intended for general use, a number of
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warning flags are provided to the ``Pass`` class. Take the
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:ref:`internal_flag_example` as an example. In the body of the constructor, we
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call ``Pass::internal()`` to set the warning flag that this is an internal; i.e.
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one aimed at Yosys *developers* rather than users. Commands with the
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``internal`` flag are often used for testing Yosys, and expose functionality
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that would normally be abstracted. Setting this flag also ensures that commands
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will be included in :doc:`/cmd/index_internal`.
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.. literalinclude:: /generated/functional/test_generic.cc
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:language: cpp
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:start-at: FunctionalTestGeneric()
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:end-at: }
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:dedent:
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:caption: `test_generic` pass constructor
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:name: internal_flag_example
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The other warning flag available is ``Pass::experimental()``, also to be called
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during the constructor. This should used for experimental commands that may be
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unstable, unreliable, incomplete, and/or subject to change. Experimental passes
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also typically have the text ``(experimental)`` at the start of their
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``short_help``, but this is not always the case.
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.. todo:: should the experimental flag add ``(experimental)`` automatically?
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In both cases, commands with these flags set will print additional warning text
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in the help output. Calling commands with the ``experimental`` flag set, will
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also call ``log_experimental()`` with the name of the pass, providing an
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additional warning any time the pass is used.
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.. note::
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When testing the handling of expected error/warning messages with e.g.
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`logger`, it is possible to disable the warnings for a given experimental
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feature. This can be done by calling Yosys with ``--experimental
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<feature>``, where ``<feature>`` is the name of the experimental pass.
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The ``Pass::help()`` method
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~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Overriding this method is the original way to provide help text, and as of this
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writing is still the most common. The ``log()`` function should be called
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directly to print and format the help text, and each line should be limited to
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80 (printed) characters. While it is possible to provide arbitrary formatting,
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it is preferred to follow the guidelines here to maintain consistency with other
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passes and to assist in correct parsing and formatting during RST generation
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(i.e. these docs).
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.. note::
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It is good practice in the ``Pass::help`` method for each call to ``log()`` to
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correspond to a single line, containing exactly one ``\n`` (at the end). This
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allows the appearance in source to match the appearance in the terminal.
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The first and last lines should always be empty, followed by the primary usage
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signature for the command. Each usage signature should be indented with 4
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spaces, and followed by an empty line. Each option or flag should start on a
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new line indented with 4 spaces, followed by a description of the option which
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is indented by a further 4 spaces, and then an empty line. Option descriptions
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typically start with lower case, and may forgo a trailing period (``.``). Where
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multiple options share a description the empty line between options should be
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omitted.
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.. note::
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`Commands JSON`_ has more on how formatting in ``help()`` gets parsed.
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The ``Pass::formatted_help()`` method
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The ``formatted_help`` method serves two purposes in help generation, both of
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which are optional. In both cases, any pass which uses the method should
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``#include "kernel/log_help.h"``, and begin the method by calling ``auto *help =
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PrettyHelp::get_current();``. The method finishes by returning a boolean value.
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``true`` means help content has been added to the current ``PrettyHelp``, while
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``false`` indicates that ``Pass::help()`` should be called instead.
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Setting a command group
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^^^^^^^^^^^^^^^^^^^^^^^
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Command groups are used when `dumping to JSON`_, so that related
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commands can be presented together in documentation. For example, all of the
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formal commands (which `chformal` is one of) are listed under
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:doc:`/cmd/index_formal`, by using the ``autocmdgroup`` directive in
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:file:`docs/source/cmd/index_formal.rst`. By default, commands are grouped by
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their source location, such that the group is the same as the path to the source
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file.
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.. note::
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Source location tracking requires :makevar:`ENABLE_HELP_SOURCE` to be set in
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the makefile. Some passes, like the ``opt_*`` family, are able to be grouped
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by the name of the pass; but most will be assigned the ``unknown`` group.
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For frontends and backends, source code is structured such that different
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formats are located in different folders. Default behavior is to instead
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group all of these passes as :doc:`/cmd/index_frontends` and
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:doc:`/cmd/index_backends` respectively. Without location tracking, the
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fallback is to look for passes that start with ``read_`` or ``write_``.
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It is possible to set the group of a command explicitly with the
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``PrettyHelp::set_group()`` method. This allows grouping of commands which may
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not share a common source location, as well as ensuring that commands are still
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grouped when location tracking is disabled. Because ``Pass::formatted_help()``
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returns if it produced help content, it is completely valid to override the
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method, get the current instance of ``PrettyHelp``, set the command group, and
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then return ``false``.
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.. warning::
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There is currently no warning available for groups that do not have a
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corresponding ``autocmdgroup``. If you add a new command group, make sure
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that it has a corresponding index page.
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Rich help text
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^^^^^^^^^^^^^^
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The second purpose of ``Pass::formatted_help`` is to provide richer help
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content which is able to take advantage of the reStructuredText formatting used
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here in the web docs. It also provides a more fluid way of writing help text,
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without getting caught up in the terminal-first spacing requirements of writing
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for ``Pass::help()``.
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Help content is a list of ``ContentListing`` nodes on a root node, which can be
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found by calling ``PrettyHelp::get_root()``. Each node has a type, a body, and
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its own list of children ``ContentListing``\ s. Adding content is done with the
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``ContentListing::{usage, option, codeblock, paragraph}`` methods, which each
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add a new child node with a type set to the calling method. Let's take a look
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at the source code for `chformal`.
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.. literalinclude:: /generated/chformal.cc
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:language: c++
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:start-at: bool formatted_help()
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:end-before: void execute
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:caption: ``ChformalPass::formatted_help()`` from :file:`passes/cmds/chformal.cc`
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:name: chformal_source
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We can see that each of the ``ContentListing`` methods have the body of the new
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node as the first argument. For a ``usage`` node, this is how to call the
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command (i.e. its usage signature). ``paragraph`` nodes contain a paragraph of
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text with line breaks added automatically; the argument itself should contain
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any line breaks, but the string can be broken across multiple lines as shown.
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The body of a ``paragraph`` node is treated as raw RST, allowing for inline
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formatting and references as if it were written in the RST file itself. As
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shown in the example (and the :ref:`formatted output above <chformal autocmd>`),
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this includes using single backticks for linking to cells or commands, and
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double backticks for raw code.
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The ``option`` method lists a single option for the command, usually starting
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with a dash (``-``). An optional second argument can be provided with adds a
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paragraph node as a child of the option, and is used for describing the option.
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Where multiple options share a description, it should be added to the last
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option.
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.. note::
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To add multiple paragraphs to an option's description,
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``ContentListing::open_option()`` should be used instead. This method
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returns the option node, which can then be used to call
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``ContentList::paragraph()`` multiple times.
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``codeblock`` content is displayed verbatim, and content should include line
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breaks as desired. No extra formatting will be applied to the text, and it will
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be rendered with a monospace font; making it perfect for code sections or ASCII
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art diagrams which render the same on the web as they do in the terminal. An
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optional second argument is available for specifying the language in RST output
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for code syntax highlighting (use ``yoscrypt`` for yosys script syntax
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highlighting).
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..
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not recommended since it (currently) doesn't render in the terminal
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The final method available is ``ContentListing::open_usage``. As with
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``open_option`` creates and returns a new node which can have additional content
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added to it directly. For the usage node, this can be used for example to add
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text/options specific to a given usage of the command. In the web documentation
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any content added in this way will be indented under the usage signature.
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..
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When :makevar:`ENABLE_HELP_SOURCE` is set, each ``ContentListing`` node also
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stores file path and line number of its source location. But I think this might
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only be used when raising errors/warnings during ``autocmd``.
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Command line rendering
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~~~~~~~~~~~~~~~~~~~~~~
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Rendering text for the command line is done by the ``Pass::help`` method. When
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this method is not overridden, the default behavior is to call
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``Pass::formatted_help()``. If this method is also left unimplemented, or the
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return value is explicitly false, then a default message about missing help text
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for the command is displayed. Returning true, however, will then call
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``PrettyHelp::log_help()`` to convert the formatted help content into plain
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text.
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.. note::
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Regardless of which help method is used, any `warning flags`_ set on the pass
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will display a message to warn the user. These are regular messages, using
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``log()`` rather than ``log_warning()``, meaning (for example) they will
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be suppressed by the ``-q`` command line option.
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Rendering rich help text as plain text is done by traversing over all the
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``ContentListing`` nodes and printing the body text. ``usage`` nodes are
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preceded by an empty line and indented one level (4 spaces). ``option`` nodes
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are also indented one level, while their children are indented an extra level (8
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spaces). Any ``codeblock`` nodes are rendered as-is at the current indentation,
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with no further formatting applied.
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``paragraph`` nodes are broken into words separated by spaces, and each word is
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printed. If a word would cause the current line to exceed 80 characters
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(controlled by ``MAX_LINE_LEN`` in :file:`kernel/log_help.cc`), then the word
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will instead be placed on a new line with the same level of indentation. Special
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handling is included for words that begin and end with a backtick (`````) so
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that these are stripped when printing to the command line. Compare
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:ref:`chformal_help` below with the :ref:`chformal autocmd` above. The content
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is still the same, but for the command line it uses a fixed width.
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.. todo:: spaces in backticks (``assert(...)`` vs ````assert(s_eventually ...)````)
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.. literalinclude:: /generated/chformal.log
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:lines: 2-
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:name: chformal_help
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:caption: Command line output for `help chformal`
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Cell help
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---------
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Unlike commands, cell help text is generated at compile time, and is not
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affected by platform or compile flags. This also means that it is not possible
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to provide help content for custom cell types in plugins or technology
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libraries.
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Two verilog simulation libraries provide models for all built-in cell types.
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These are defined in :file:`techlibs/common/simcells.v` (for
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:doc:`/cell/index_gate`) and :file:`techlibs/common/simlib.v` (for
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:doc:`/cell/index_word`). Each model is preceded by a structured comment block,
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formatted as either :ref:`v1` or :ref:`v2`. These comment blocks are processed
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by a python script, :file:`techlibs/common/cellhelp.py`, to generate the help
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content used in :file:`kernel/register.cc`.
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.. note::
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Each verilog module (and its comment block) is parsed into a C++ ``dict``,
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mapping the cell type (the name of the verilog module) to a ``SimHelper``
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struct in :file:`kernel/register.cc` with ``#include``\ s. Calling `help
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<celltype>` then retrieves the corresponding ``SimHelper`` and displays the
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help text contained.
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Calling `help -cells` will list all built-in cell types with their input/output
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ports. There is again an unlisted :ref:`cell index <cellindex>` which shows all
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cell types with their title. Unlike commands, providing a title is optional,
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and only available with `v2`_ formatting, so most just use the name of the cell
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(qualified with the containing group). It is also possible to display the
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verilog simulation model by calling `help <celltype>+`.
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.. _v1:
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v1 (default)
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~~~~~~~~~~~~
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As mentioned previously, the verilog simulation models are preceded by a
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structured comment block. Each line starting with ``//-`` is added to the
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description of the next verilog module. Non-empty lines must have a space after
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the dash before text, and should be limited to 80 characters (84 including the
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``//-``). The description is rendered to the terminal as-is when calling `help
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<celltype>`, while the web docs will render it as text, with empty lines being
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used to separate paragraphs.
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..
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Descriptions can extend into the verilog module itself, including *all* comment
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lines that start with a dash prior to the ``endmodule``. However, everything in
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the ``module .. endmodule`` block is considered source code, so this is not
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recommended.
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.. note::
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Most of the legacy cell descriptions include a signature line (``//-
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$<celltype> (<ports>)``). More recent versions of the help generation will
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automatically produce this signature from the verilog declaration, making
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this an optional inclusion. Note that if a signature line *is* included, it
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*must* start with at least 4 spaces (not tabs), and include one empty line
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(``//-``) before and after.
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Each cell type must also be assigned a group, failing to do so will produce an
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error. This can be done by adding ``//* group <cellgroup>`` anywhere in the
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comment block. As with commands, the group determines where the cell appears in
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the Sphinx documentation, but does not otherwise impact the output of `help`. As
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with commands, there is no warning produced if cells are assigned a group which
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is not used in the documentation. Make sure to check :file:`docs/source/cell`
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for the groups currently available.
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For the cell models in :file:`techlibs/common/simcells.v`, it is possible to
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provide a truth table at the end of the cell description which is rendered in
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sphinx docs as a literal code block. We can look at the :ref:`NOT_module` to
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see this in action.
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.. literalinclude:: /generated/simcells._NOT_.v
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:language: verilog
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:start-at: //-
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:end-at: module \$_NOT_
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:name: NOT_module
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:caption: `$_NOT_` cell comment block from :file:`techlibs/common/simcells.v`
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..
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v1 descriptions in :file:`techlibs/common/simcells.v` have their version
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unconditionally changed to ``2a`` to facilitate the truth table rendering,
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making use of the v2 handling of codeblocks with ``::``. This also means A.
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using ``::`` on its own in a v1 (gate-level) description should be avoided, and
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B. *all* text after the ``"Truth table:"`` line is included in the codeblock.
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.. _v2:
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v2 (more expressive)
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~~~~~~~~~~~~~~~~~~~~
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Fields can be directly assigned with a ``//* <name> <value>`` comment line. We
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saw this in the `v1`_ format with the group, but this is actually possible with
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*all* fields of the ``SimHelper`` struct. In order to use the extra fields,
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``ver`` must be explicitly set as ``2``. The extra fields available are as
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follows, with an example provided by the :ref:`nex_module`.
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- title
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A short title for the cell, equivalent to ``short_help`` in commands.
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Rendered before the description and when hovering over links in
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documentation.
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- tags
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A space-separated list of :doc:`/cell/properties`. Not used in `help`
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output, but provided when dumping to JSON and in the Sphinx docs.
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.. literalinclude:: /generated/simlib.nex.v
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:language: verilog
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:name: nex_module
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:caption: `$nex` cell comment block from :file:`techlibs/common/simlib.v`
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.. warning::
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While it is possible to assign values to any of the ``SimHelper`` fields,
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some fields are automatically assigned and explicitly setting them may result
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in errors, or discarding of the assigned value. These fields are the name,
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ports, code, source, and desc.
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The cell description is provided in the same way as in `v1`_, with each line
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starting with a ``//-``. When generating the Sphinx documentation, the cell
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description is interpreted as raw RST. This allows both in-line formatting like
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linking to commands or passes using backticks (`````), and literal code blocks
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with the ``::`` marker as in the following example:
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.. tab:: Verilog comment
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.. code-block:: verilog
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//- text
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//- ::
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//-
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//- monospaced text
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//-
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//- indentation and line length will be preserved, giving a scroll bar if necessary for the browser window
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//-
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//- more text
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.. tab:: formatted output
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text
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::
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monospaced text
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indentation and line length will be preserved, giving a scroll bar if necessary for the browser window
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more text
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Note that the empty line after the ``::`` and before the text continues are
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required, as is the indentation before the literal contents. When rendering to
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the terminal with `help <celltype>`, the ``::`` line will be ignored, while
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Sphinx displays the section verbatim like shown.
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.. todo:: in line formatting for web docs isn't exclusive to v2,
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but it does raise the question of if we should be doing something to prevent
|
|
v1 descriptions being treated as raw RST.
|
|
|
|
|
|
Dumping to JSON
|
|
---------------
|
|
|
|
Once compiled, Yosys is able to dump both the internal command and cell
|
|
libraries to a machine-readable JSON file. Primarily intended for building this
|
|
documentation (more on that in the next section), this feature is not advertised
|
|
within Yosys itself, and can be done with `help -dump-cmds-json <cmds.json>` and
|
|
`help -dump-cells-json <cells.json>` respectively.
|
|
|
|
Both JSON files are formatted very similarly, containing a single object. The
|
|
object has a ``version`` field which disambiguates between the two, a
|
|
``generator`` field which contains the Yosys version string used, a ``groups``
|
|
object which maps each group to the list of commands/cells in that group, and
|
|
finally a ``cmds`` or ``cells`` object which maps each command/cell to its help
|
|
content.
|
|
|
|
Commands JSON
|
|
~~~~~~~~~~~~~
|
|
|
|
Lets take a look at :ref:`chformal_json` as an example. We can see the bulk of
|
|
the object is taken up by the ``content`` field, which contains all the
|
|
``ContentListing`` nodes we added in :ref:`the formatted_help method for
|
|
chformal <chformal_source>`, maintaining the structure of those nodes. The
|
|
command's ``short_help`` is given in the ``title`` field, with other fields for
|
|
the `Warning flags`_, source location, source function, and corresponding group
|
|
(either implicit or explicit).
|
|
|
|
.. literalinclude:: /generated/cmds.json
|
|
:language: json
|
|
:start-at: "chformal": {
|
|
:end-before: "chparam": {
|
|
:caption: `chformal` in generated :file:`cmds.json`
|
|
:name: chformal_json
|
|
|
|
Every command registered in Yosys (including those from currently installed
|
|
plugins) has a corresponding object in the JSON dump. For commands where
|
|
``Pass::formatted_help()`` is unimplemented or returns false, ``ContentListing``
|
|
nodes will be generated by parsing the unformatted ``Pass::help()`` output. This
|
|
is largely the same as `Command line rendering`_ but in reverse, with a few
|
|
simple rules to try convert between raw text and the different node types.
|
|
|
|
To be parsed as a ``usage`` node, the current line:
|
|
+ must start with the name of the command (case sensitive), followed by a
|
|
space or a new line;
|
|
+ may have up to four characters of whitespace as indentation;
|
|
+ must be the first non-empty line, preceded by two empty lines, or
|
|
immediately following another usage signature with the same indentation.
|
|
|
|
Any lines immediately after a usage signature which is indented more than the
|
|
signature will be appended to the usage signature. This allows for breaking
|
|
arguments across lines in the terminal output while still producing a single
|
|
``usage`` node.
|
|
|
|
.. code-block:: cpp
|
|
:caption: Example code for a command with multiple usage signatures
|
|
|
|
log("\n");
|
|
log(" command\n");
|
|
log(" command -argument\n");
|
|
log(" -another argument\n");
|
|
log("\n");
|
|
log("\n");
|
|
log("command description.\n"); // not a signature because it is dedented
|
|
log("\n");
|
|
log("\n");
|
|
log(" command -different argument\n");
|
|
log("\n");
|
|
|
|
If a line is indented and starts with a dash (``-``), and does not immediately
|
|
follow a usage signature, it is parsed as an ``option`` node. Anything else is
|
|
parsed as a ``codeblock`` and added to either the root node or the current
|
|
option depending on the indentation. This allows yosys script syntax
|
|
highlighting for (most) options, while still respecting help content which
|
|
relies on the fixed-width rendering.
|
|
|
|
To enable syntax highlighting in synthesis command scripts, if the final block
|
|
of help output starts with the string ``"The following commands are executed by
|
|
this synthesis command:\n"``, then the rest of the code block is formatted as
|
|
``yoscrypt`` (e.g. `synth_ice40`). The caveat here is that if the ``script()``
|
|
calls ``run()`` on any commands *prior* to the first ``check_label`` then the
|
|
auto detection will break and revert to unformatted code (e.g.
|
|
`synth_fabulous`).
|
|
|
|
|
|
Cells JSON
|
|
~~~~~~~~~~
|
|
|
|
Dumping the cell help contents to JSON follows a very similar format as the
|
|
``SimHelper`` struct. The main difference is that there is no ``ver`` or
|
|
``group`` field, and the ``tags`` have become ``properties``. Each cell type
|
|
also has a corresponding ``CellType`` struct defined in
|
|
:file:`kernel/celltypes.h` which we now have access to. This allows us to
|
|
distinguish which ports are inputs and which are outputs, as well as some extra
|
|
property flags. The :ref:`nex_json` is reproduced here to show this
|
|
transformation.
|
|
|
|
.. literalinclude:: /generated/cells.json
|
|
:language: json
|
|
:start-at: "$nex": {
|
|
:end-at: },
|
|
:caption: `$nex` in generated :file:`cells.json`
|
|
:name: nex_json
|
|
|
|
|
|
Working with Sphinx
|
|
-------------------
|
|
|
|
This documentation is built on Sphinx using `reStructuredText`_. To support the
|
|
rich documentation of commands and cells in Yosys, as well as the Yosys
|
|
scripting language and RTLIL, we use some custom extensions and will touch on
|
|
those here.
|
|
|
|
.. _reStructuredText: https://docutils.sourceforge.io/rst.html
|
|
|
|
Sphinx uses `Pygments`_ for syntax highlighting code blocks, for which we
|
|
provide to additional lexers. The first of these is ``RTLIL`` for the
|
|
:doc:`/yosys_internals/formats/rtlil_rep`, and is exclusive to the Yosys docs.
|
|
The second lexer, ``yoscrypt``, is for :doc:`/getting_started/scripting_intro`
|
|
and is available across all of the YosysHQ docs through `furo-ys`_, our custom
|
|
fork of the `furo`_ theme for Sphinx. These languages are automatically
|
|
associated with the ``.il`` and ``.ys`` file extensions respectively, and can be
|
|
selected for use in any ``literalinclude`` or ``code-block`` segments.
|
|
|
|
.. _Pygments: https://pygments.org/
|
|
.. _furo-ys: https://github.com/YosysHQ/furo-ys/
|
|
.. _furo: https://github.com/pradyunsg/furo
|
|
|
|
To simplify inline Yosys script syntax highlighting, these docs provide the
|
|
``yoscrypt`` role. This role renders (e.g.) ``:yoscrypt:`chformal -remove```
|
|
into :yoscrypt:`chformal -remove`. For linking to command and cell
|
|
documentation, we also use a default role of ``autoref``. Any text in single
|
|
backticks without an explicit role will be assigned this one. We've already
|
|
seen this being used above in the help text for `chformal` and `$nex` (which
|
|
were themselves written as ```chformal``` and ```$nex``` respectively).
|
|
|
|
By using the `autodoc extension`_ and two custom `Sphinx Domains`_ (more on them
|
|
later), ``autoref`` is able to produce links to any commands or cells available
|
|
in Yosys. So long as there are no spaces in the text, and it doesn't begin with
|
|
a dash (``-``), it will try to convert it to a link. If the text begins with
|
|
``$`` then it will use the ``cell:ref`` role, otherwise it will use ``cmd:ref``.
|
|
Let's take a look at some examples:
|
|
|
|
.. _Sphinx Domains: https://www.sphinx-doc.org/en/master/usage/domains/index.html
|
|
.. _autodoc extension: https://www.sphinx-doc.org/en/master/usage/extensions/autodoc.html
|
|
|
|
.. tab:: reStructuredText
|
|
|
|
.. literalinclude:: formatting_sample.txt
|
|
:language: reStructuredText
|
|
:start-after: .. 1
|
|
:end-before: .. 2
|
|
|
|
.. tab:: formatted output
|
|
|
|
.. include:: formatting_sample.txt
|
|
:start-after: .. 1
|
|
:end-before: .. 2
|
|
|
|
The ``autoref`` role also works with two words, if the first one is "help":
|
|
|
|
.. tab:: reStructuredText
|
|
|
|
.. literalinclude:: formatting_sample.txt
|
|
:language: reStructuredText
|
|
:start-after: .. 2
|
|
:end-before: .. 3
|
|
|
|
.. tab:: formatted output
|
|
|
|
.. include:: formatting_sample.txt
|
|
:start-after: .. 2
|
|
:end-before: .. 3
|
|
|
|
And if the text begins with a dash, or doesn't match the "help" formatting, it
|
|
will fallback to formatting as inline yoscrypt.
|
|
|
|
.. tab:: reStructuredText
|
|
|
|
.. literalinclude:: formatting_sample.txt
|
|
:language: reStructuredText
|
|
:start-after: .. 3
|
|
|
|
.. tab:: formatted output
|
|
|
|
.. include:: formatting_sample.txt
|
|
:start-after: .. 3
|
|
|
|
Using autodoc
|
|
~~~~~~~~~~~~~
|
|
|
|
- below is the raw RST output from ``autocmd`` (``YosysCmdDocumenter`` class in
|
|
:file:`docs/util/cmd_documenter.py`) for `chformal` command
|
|
- heading will be rendered as a subheading of the most recent heading (see
|
|
`chformal autocmd`_ above rendered under `Command help`_)
|
|
- ``.. cmd:def:: <cmd>`` line is indexed for cross references with ``:cmd:ref:``
|
|
directive (`chformal autocmd`_ above uses ``:noindex:`` option so that
|
|
`chformal` still links to the correct location)
|
|
|
|
+ ``:title:`` option controls text that appears when hovering over the
|
|
`chformal` link
|
|
|
|
- commands with warning flags (experimental or internal) add a ``.. warning``
|
|
block before any of the help content
|
|
- if a command has no ``source_location`` the ``.. note`` at the bottom will
|
|
instead link to :doc:`/cmd/index_other`
|
|
|
|
.. _showing autocmd generated rst:
|
|
|
|
.. autocmd_rst:: chformal
|
|
|
|
- command groups documented with ``autocmdgroup <group>``
|
|
|
|
+ with ``:members:`` option this is the same as calling ``autocmd`` for each
|
|
member of the group
|
|
|
|
- ``autocell`` and ``autocellgroup``
|
|
|
|
+ very similar to ``autocmd`` and ``autocmdgroup`` but for cells instead of
|
|
commands (``YosysCellDocumenter`` in :file:`docs/util/cell_documenter.py`)
|
|
+ optionally includes verilog source for cell(s) with ``:source:`` option
|
|
(plus ``:linenos:``)
|
|
+ cell definitions do not include titles
|
|
+ cells can have properties (:ref:`propindex`)
|
|
|
|
- bonus ``autocmd_rst``, used exclusively on this page for `showing autocmd
|
|
generated rst`_
|
|
|
|
Our custom Sphinx domains
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
- ``cmd`` and ``cell``
|
|
- Directives
|
|
|
|
+ ``cmd:def`` provide command definition
|
|
+ ``cmd:usage`` used by ``autocmd`` for command usage signatures
|
|
+ ``cell:def`` provide cell definition
|
|
+ ``cell:defprop`` provide cell property definition (used in
|
|
:doc:`/cell/properties`)
|
|
+ ``cell:source`` used by ``autocell`` for simulation models
|
|
|
|
- Roles
|
|
|
|
+ ``cmd:ref`` link to a ``cmd:def`` with the same name
|
|
+ ``cmd:title`` same as ``cmd:ref``, but includes the short help in the text
|
|
|
|
- ``:cmd:title:`chformal``` -> :cmd:title:`chformal`
|
|
|
|
+ ``cell:ref`` link to a ``cell:def`` with the same name
|
|
+ ``cell:title``
|
|
|
|
- ``:cell:title:`$nex``` -> :cell:title:`$nex`
|
|
|
|
+ ``cell:prop`` link to a ``cell:defprop`` of the same name
|