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MIT Scheme allows the length of a string to be dynamically adjusted in a
limited way. This feature works as follows. When a new string is
allocated, by whatever method, it has a specific length. At the time of
allocation, it is also given a maximum length, which is guaranteed
to be at least as large as the string's length. (Sometimes the maximum
length will be slightly larger than the length, but it is a bad idea to
count on this. Programs should assume that the maximum length is the
same as the length at the time of the string's allocation.) After the
string is allocated, the operation set-string-length! can be used
to alter the string's length to any value between 0 and the string's
maximum length, inclusive.
procedure+: string-maximum-length string
Returns the maximum length of string. The following is guaranteed:
(<= (string-length string)
(string-maximum-length string)) => #t
The maximum length of a string never changes.
procedure+: set-string-length! string k
Alters the length of string to be k, and returns an
unspecified value. K must be less than or equal to the maximum
length of string. set-string-length! does not change the
maximum length of string.
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