`cen % %cen`
============
Pulling
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The `%` runes [pull]() [`++arms`]() and [`++wings`]() from the
[subject](), often modifying their values. The `%` runes are similar to
function calls, or execution tools. We use them to either compute some
code with changes in the subject, or produce the output from a core.
There are two categories of `%` runes.
#### Pull with changes:
[`%=`]() The natural `%` rune. Evaluates `p` with the changes specified
in `q`.
[`%_`]() Evaluates `p` with the changes specified in `q`, then
casts the product back to the type of `p`.
[`%*`]() Evaluates `p` from a [door]() `q` with changes `r`.Terminated by `==`.
### Pull the empty arm `$`, similar to calling a function:
[`%-`]() [slams]() a core with one argument.
[`%+`]() slams a core with two arguments.
[`%^`]() slams a core with three arguments.