Metamath Proof Explorer


Theorem wrdfsupp

Description: A word has finite support. (Contributed by Thierry Arnoux, 27-May-2025)

Ref Expression
Hypotheses wrdfsupp.1 φ Z V
wrdfsupp.2 φ W Word S
Assertion wrdfsupp φ finSupp Z W

Proof

Step Hyp Ref Expression
1 wrdfsupp.1 φ Z V
2 wrdfsupp.2 φ W Word S
3 eqidd φ W = W
4 3 2 wrdfd φ W : 0 ..^ W S
5 fzofi 0 ..^ W Fin
6 5 a1i φ 0 ..^ W Fin
7 4 6 1 fdmfifsupp φ finSupp Z W