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The AddTemporary command creates a temporary entry associating key with value in a cache table. The cache table can be given directly as cache, or cache can refer to a procedure that has, or can have, a cache remember table. If such a procedure is given and it has a cache remember table, the temporary entry is inserted into that table. Otherwise, a new cache table is created, installed as cache's remember table and the temporary entry is inserted into that table.

To handle an expression sequence as a key, key must be given in a list . The actual key used for the entry is op(key).

If more than one argument is passed after key, then an expression sequence containing those arguments is used as value.

Assigning directly into a cache table, using the cache[key] := value notation, creates a temporary entry. As well, a function with option cache creates a temporary entry when the function is called. Calling AddPermanent is the only way to create a permanent entry into a cache table.

To remove a temporary entry from a cache table use RemoveTemporary .

Creating a temporary entry for a key that already has a permanent entry is not an error. In this case, the temporary entry is used.

For more information on cache tables, see Cache Package .

$\mathrm{c1}≔\mathrm{Cache}\left(\right)$

$\mathrm{c1}≔\mathrm{Cache}\left(512\right)$

$\mathrm{c1}\left[a\right]≔b$

${\mathrm{c1}}_a≔b$

$\mathrm{Cache}:-\mathrm{AddTemporary}\left(\mathrm{c1}\,\left[x\right]\,y\right)$

$\mathrm{Cache}:-\mathrm{AddTemporary}\left(\mathrm{c1}\,\left[y\right]\,z\right)$

$\mathrm{eval}\left(\mathrm{c1}\right)$

$\mathrm{Cache}\left(512\,'\mathrm{temporary}'=\left[x=y\,a=b\,y=z\right]\right)$

p := proc(x,y) option cache; x+y; end proc;

$p≔\mathbf{proc}\left(x\,y\right)\mathbf{option}\mathrm{cache}\;x\+y\mathbf{end\; proc}$

$p\left(1\,1\right)$

$2$

$\mathrm{Cache}:-\mathrm{AddTemporary}\left(p\,\left[2\,2\right]\,8\right)$

$\mathrm{Cache}:-\mathrm{AddTemporary}\left(p\,\left[1\,2\right]\,5\right)$

$p\left(2\,2\right)$

$8$

$p\left(1\,2\right)$

$5$

$\mathrm{Cache}:-\mathrm{AddPermanent}\left(p\,\left[3\,3\right]\,5\,6\,7\right)$

$p\left(2\,2\right)$

$8$

$\mathrm{op}\left(4\,\mathrm{eval}\left(p\right)\right)$

$\mathrm{Cache}\left(512\,'\mathrm{temporary}'=\left[\left(1\,1\right)=2\,\left(1\,2\right)=5\,\left(2\,2\right)=8\right]\,'\mathrm{permanent}'=\left[\left(3\,3\right)=\left(5\,6\,7\right)\right]\right)$