lt;|rdfs:Resource| MyResource&gt;<br/>gx-user(18): (slot-value 
MyResource 'myProp)<br/>"original one"<br/>gx-user(19): (put-value MyResource 
myProp "added 1st")<br/>("added 1st" "original one")<br/>gx-user(20): (put-value 
MyResource myProp "added 2nd")<br/>("added 2nd" "added 1st" "original 
one")<br/>gx-user(21): (slot-value MyResource 'myProp)<br/>("added 2nd" "added 
1st" "original one")<br/></code>
<p>When you add same value that is already stored in the slot, nothing 
happens.</p>
<code face=monospa