9.2. What Limits to Choose?

A limit must not be perceived as an absolute limit, the
implementor is free to increase the limit. To some extent, the
implementor may also decrease the limit, in which case this must
be properly documented as a non-standard feature. Also, the reason
for this should be noted in the documentation.

Many interpreters are likely to have “memory” as an implementation
limit, meaning that they will allow any size as long as there is
enough memory left. Actually, this is equivalent to no limit,
since running out of memory is an error with limit enforcing
interpreters as well. Some interpreters let the user set the
limits, often controlled through the OPTIONS instruction.

For computers, limit choices are likely to be powers of two, like
256, 1024, 8192, etc. However, the REXX language takes the side of
the user, and defines the limits in units which looks as more
“sensible” to computer non-experts: most of the limits in REXX are
numbers like 250, 500, 1000, etc.




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