LABEL command
1. To edit the text shown when the user taps on a gate in CNFG mode,
use the LABEL command. This command runs a simple text editor.
To exit the editor, press Control-C.
2. The labels editor lets you move the cursor with the arrow keys,
delete or insert a line using the Control-F and RETURN keys, insert
characters, or erase characters with Control-G. (Currently, there
is no way to recover a deleted line, or to move or copy lines except
by retyping them.)
3. Any line without a colon (":") is displayed as-is on the screen
when the gate is configured. To include a colon in a label, use
a double colon ("::").
4. If a line does contain a colon, it describes an attribute.
Everything to the left of the colon is a coded string showing
the name, type, and default value of the attribute. Everything
after the colon is shown as-is as the label for the attribute.
Blanks are ignored between parts of the attribute information.
':'
5. The name is optional, and must be enclosed in square brackets.
Actually, several bracketed names may be used if for some
reason the attribute must have several names. The code for a
gate may refer to an attribute by its name, or by an integer
index ranging from 1 to the number of attributes.
6. The type is a single capital letter. The following types are
defined:
I Integer. If a precision is given, the number is
blank-padded to at least that width when displayed.
If a default is given, it becomes the initial value
of the attribute for newly created gates. If there
is no default, the attribute is initially blank.
H Hexadecimal integer. The number is zero-padded to at
least the specified width; if no precision is given
but there is a default, the precision is equal to the
number of digits in the default.
R Real number. The precision gives the number of decimal
places shown on the number; if no precision is given
the number will be shown in floating format. Large
and small numbers are shown in scientific notation.
U Real number with units. The default is of the form,
','
where the comma and default may be omitted if the
attribute should be blank by default. The number is
shown followed by the units-string; large and small
numbers are shown using standard engineering notation
abbreviations. The attribute:
[clock-freq] 2FHz,10000:Clock frequency::
will display its default as "10KHz".
F Real number with units, scientific notation. This is
just like "U" format except large and small numbers
are shown in scientific notation with the units-string
appended.
C String attribute. The precision specifies the number
of characters of length the string may have; with no
precision the string length is unlimited. The default
may be any string of characters, unmodified except that
leading and trailing blanks are removed.
A String attribute. To the user, this is just like a
"C" type attribute with no precision specified.
Internally, this is stored as a variable-length
string, whereas a "C" type attribute is stored as a
fixed length string. Precision is ignored.
B Boolean value. The default may be "Y" or "N" (or "T"
or "F") to specify true or false. If the default is
blank (or "X"), the attribute is initially blank.
If the default is "T" or "F" or "X", the attribute is
displayed as "True" or "False". If the default is
"Y" or "N" or blank, the attribute is displayed as
"Yes" or "No".
V Variant. This attribute represents a choice among
several named options. The default string is actually
a sequence of comma-separated phrases. These phrases
are numbered from 0. The precision actually specifies
the default variant shown; with no precision, variant 0
is the default. If the attribute should be able to be
blank, simply leave one of the phrases empty.
1 V , Yes, No, Maybe : What do you think?
This attribute takes on one of the four values blank,
Yes, No, or Maybe; it is initially Yes.
7. A variant name may be included in any attribute, followed by a
semicolon. The name must be one of the options for a variant
attribute that precedes this attribute in the list. The attribute
will be invisible unless the proper variant was selected.
V Square,Circle: Kind of shape::
Square; R:Width::
Square; R:Height::
Circle; R:Radius::
8. If the type letter is preceded by the letter 'O', the attribute is
optional and can be made blank by typing a blank line. An attribute
with no default is always optional. If the attribute has a default
and is not optional, then it must always have a nonblank value. (This
is true even of string attributes.) Entering a blank line for a
nonoptional attribute restores the default value.
Email lazzaro@cs.berkeley.edu
Phone (510) 643 4005
SMail UC Berkeley / CS Division / 387 Soda Hall / Berkeley CA 94720