Syntax
where S is the name of a string, and N is the string.
Strings are sequences of alphanumeric characters of a length varying
between zero and currently 253 characters. It is possible to define
strings having length zero, which we term empty strings. Strings are
mostly used (1) to define quantities that might take different values
for different parts of a [B/D] program; (2) as shorthand for some long
sequence of characters. Some example definitions are
Commonly, command lines have leading and trailing spaces removed, and
then other spaces (except the space separating command from arguments)
are ignored and remaining characters converted to lower case. However,
the STRING: command is an exception: space and case conversions
carried out only as necessary. This allows the definition part to be
used for titles, further commands, and so forth, where the retention of
case or spacing might be crucial: when the string is actually used,
parsing will be carried out in the usual way.
The names of strings are subjected to space and case
conversions, so that the two string names `TEXT1' and `text1' are
equivalent. Substrings (see below) are, however, parsed completely. A
string defined with the same name as a pre-existing string simply
overwrites the former definition. String definitions can be checked by
issuing the LOOK: command with argument s . (When you do
this, notice that
a good deal of [B/D] output has names printed with the first character
capitalised - this is cosmetic only.)
