diff options
Diffstat (limited to 'luatexbase-attr.dtx')
| -rw-r--r-- | luatexbase-attr.dtx | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/luatexbase-attr.dtx b/luatexbase-attr.dtx index d19240b..c6a7040 100644 --- a/luatexbase-attr.dtx +++ b/luatexbase-attr.dtx @@ -443,7 +443,11 @@ end luatexbase.unset_attribute = unset_attribute % \end{macrocode} % -% User whatsit allocation (experimental). +% Allocation of user-defined whatsit nodes (experimental). +% User-defined whatsit nodes (or user whatsits) are ignored by the +% \luatex engine. They can thus be used to store information in +% node lists without doing any harm. User whatsits can be +% distinguished by an id that is stored in node field |user_id|. % % \begin{macrocode} --- cf. luatexref-t.pdf, sect. 8.1.4.25 @@ -457,18 +461,18 @@ local anonymous_whatsits = 0 local anonymous_prefix = "anon" % \end{macrocode} % -% The whatsit allocation is split into two functions: +% User whatsit allocation is split into two functions: % \verb|new_user_whatsit_id| registers a new id (an integer) % and returns it. It is up to the user what he actually does % with the return value. % -% Registering whatsits without a name, though supported, is +% Registering user whatsits without a name, though supported, is % not exactly good style. In these cases we generate a name % from a counter. % -% In addition to the whatsit name, it is possible and even +% In addition to the user whatsit name, it is possible and even % encouraged to specify the name of the package that will be -% using the whatsit as the second argument. +% using the user whatsit as the second argument. % % \begin{macrocode} --- string -> string -> int @@ -512,7 +516,7 @@ luatexbase.new_user_whatsit_id = new_user_whatsit_id % \end{macrocode} % % \verb|new_user_whatsit| first registers a new id and then also -% creates the corresponding whatsit of subtype “user defined”. +% creates the corresponding whatsit node of subtype “user-defined”. % We return a nullary function that delivers copies of the whatsit. % % \begin{macrocode} @@ -528,7 +532,7 @@ luatexbase.new_user_whatsit = new_user_whatsit luatexbase.new_user_whatsit_factory = new_user_whatsit --- for Stephan % \end{macrocode} % -% If one knows the name of a whatsit, its corresponding id +% If one knows the name of a user whatsit, its corresponding id % can be retrieved by means of \verb|get_user_whatsit_id|. % % \begin{macrocode} @@ -545,11 +549,11 @@ luatexbase.get_user_whatsit_id = get_user_whatsit_id % The inverse lookup is also possible via \verb|get_user_whatsit_name|. % Here it finally becomes obvious why it is beneficial to supply a package % name -- it adds information about who created and might be relying on the -% whatsit in question. First return value is the whatsit name, the second -% the package identifier it was registered with. +% user whatsit in question. First return value is the user whatsit name, the +% second the package identifier it was registered with. % -% We issue a warning and return empty strings in case the asked whatsit is -% unregistered. +% We issue a warning and return empty strings in case the argument +% doesn't correspond to a registered user whatsit id. % % \begin{macrocode} --- int | fun | node -> (string, string) |