Assigning fields matched in sed to a variable

The regex matched in the first set of brackets is referenced by the \1
The regex matched in the second set of brackets is referenced by the \2

echo "user=clarkeb role=admin" | sed 's/\w*=\(\w*\) \w*=\(\w*\)/\1/'

Will output clarkeb

echo "user=clarkeb role=admin" | sed 's/\w*=\(\w*\) \w*=\(\w*\)/\2/'

Will output admin

echo "user=clarkeb role=admin" | sed 's/\w*=\(\w*\) \w*=\(\w*\)/\1 \2/'

Will output clarkeb admin

Therefore, outputs can be assigned to variables as you'd expect ...

myUser=$(echo "user=clarkeb role=admin" | sed 's/\w*=\(\w*\) \w*=\(\w*\)/\1/')

or

myUser=`echo "user=clarkeb role=admin" | sed 's/\w*=\(\w*\) \w*=\(\w*\)/\1/'`