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Tie::SubstrHash(3)     Perl Programmers	Reference Guide	    Tie::SubstrHash(3)

       Tie::SubstrHash - Fixed-table-size, fixed-key-length hashing

	   require Tie::SubstrHash;

	   tie %myhash,	'Tie::SubstrHash', $key_len, $value_len, $table_size;

       The Tie::SubstrHash package provides a hash-table-like interface	to an
       array of	determinate size, with constant	key size and record size.

       Upon tying a new	hash to	this package, the developer must specify the
       size of the keys	that will be used, the size of the value fields	that
       the keys	will index, and	the size of the	overall	table (in terms	of
       key-value pairs,	not size in hard memory). These	values will not	change
       for the duration	of the tied hash. The newly-allocated hash table may
       now have	data stored and	retrieved. Efforts to store more than
       $table_size elements will result	in a fatal error, as will efforts to
       store a value not exactly $value_len characters in length, or reference
       through a key not exactly $key_len characters in	length.	While these
       constraints may seem excessive, the result is a hash table using	much
       less internal memory than an equivalent freely-allocated	hash table.

       Because the current implementation uses the table and key sizes for the
       hashing algorithm, there	is no means by which to	dynamically change the
       value of	any of the initialization parameters.

       The hash	does not support exists().

perl v5.35.11			  2022-03-27		    Tie::SubstrHash(3)


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