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Help is available to the User of an Application Program in several ways.
Each Verb Group may have associated with it a Help Text File using the same
format as a normal VAX/VMS Help File. This format is discussed in the next
Section.
Note that such a file should only contain information about the Verbs within
a Group, and a separate file should be defined for each Verb Group within a
complex program.
If such a Help File is not defined, then only a restricted help is available,
being limited to a display of the Verbs within the Group, together with a list
of their Qualifiers. Each Menu contains inherently some basic help information,
being the descriptive text on each Menu Button, and this may be combined
with Verb Help if so desired.
The question mark character ``?" is used as a ``Request for Help" from the
User of an Application Program. Its action may be modified in several ways by
concatenating it with a word. The valid syntaxes are:-
- ?UIPACK
- This causes general UIPACK help to be displayed. No truncation
is allowed, but either upper or lower case may be used.
- ?
-
In Prompted Input Mode this will display the valid syntax for responding
to the request for input. Thus for a request for Integer input it describes the
valid response formats.
In Command Line mode this will display a complete list of all the
available Command Verbs, without expanding on any of them. Thus, just the
list of valid Verbs is displayed, not any Help Text associated with them.
In Menu Mode (especially Prompted and Scroll Modes), this will display
(or redisplay) the Menu, detailing the Button Numbers, the Descriptive
text associated with each Button, and (for Action Menus only), the Response
text associated with each Button.
- ?n
- Where ``n" is a Decimal Integer. This is only valid in Menu Mode
and will display the Descriptive Text (and any Response Text) associated
with the specified Menu Button.
- ?n:m
- Where ``n" and ``m" are Decimal Integers. This is only valid in
Menu Mode and will display the Descriptive Text (and any Response Text)
associated with the specified Range of Menu Buttons.
- ?Verb
- Where ``Verb" is a Verb Name (or truncation thereof). This
will attempt to scan a Help File for the current Verb Group. If no such file
has been defined, then only a list of the Qualifiers associated with the
specified Verb will be displayed. If a Help File exists, and the Verb exists
within the Help File, then the full Help facility will be used to display
whatever information is available. In the case where the Verb Name is ambiguous,
the first matching Verb within the Help File will be used.
This form of Help may be extended to display subtopics (if any are defined for
the Verb in question), by extending the syntax as shown in the following
example:-
- ?Verb/Qualifier
- \
- ?Verb Parameter
-
where ``Qualifier" is a valid Qualifier for the Verb, and ``Parameter" is
a valid subtopic for the Verb.
- ?&
- This will display a list of the currently defined Symbols and
their Equivalence Text Strings. Locked Symbols will be highlighted.
- ?&abc
- This will display a list of the currently defined Symbols
commencing with the characters ``abc..." and their Equivalence Text Strings.
- ?&&
- This will display general Symbol Help, describing how to
dynamically define a new Symbol, drop an existing one etc.
Help requests are hierarchical, such that the information for each Verb
may be split into sections giving more detailed information about subtopics
associated with the Verb. After displaying the Help information, the User
will be prompted to supply a new subtopic. A null response (just hitting the
``Return" key) will backup to the previous level, whilst typing Ctrl-Z (on
a VAX) will return immediately to the Application Program.
An Application Programmer cannot disable the response to a ``?" request, but
can optionally specify an alternate character string which will cause an
identical response. This string may be up to 8 characters in length and
may not contain any embedded spaces or tabs. It is highly recommended that it
contain at least one character that is disallowed within Verbs and Qualifiers
so as to avoid conflicts with these.
In addition to the above, there is a Subprogram (UI_GET_HELP) that may be
used to prompt for a topic (a Verb within the currently setup Verb Group)
and then display the Help Information associated with that topic.
Help information will be displayed in different manners depending on the
current mode of operation of UIPACK. In Prompted and Scroll Mode, Help
information is directly displayed on the screen, scrolling until the screen is
full or all the help information has been displayed. If the screen becomes full
the operator may request more help information by hitting the RETURN key.
In Viewport Modes, Help information is displayed within a Viewport on the screen
(see the later Section on Viewports for discussion of their use) rather than
scrolling the complete screen.
Next: Format of a
Up: Contents
Previous: Contents
Liz Buckle
Fri Jan 13 17:37:44 CST 1995