Metamath Proof Explorer


Theorem wrdfsupp

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

Ref Expression
Hypotheses wrdfsupp.1 ( 𝜑𝑍𝑉 )
wrdfsupp.2 ( 𝜑𝑊 ∈ Word 𝑆 )
Assertion wrdfsupp ( 𝜑𝑊 finSupp 𝑍 )

Proof

Step Hyp Ref Expression
1 wrdfsupp.1 ( 𝜑𝑍𝑉 )
2 wrdfsupp.2 ( 𝜑𝑊 ∈ Word 𝑆 )
3 eqidd ( 𝜑 → ( ♯ ‘ 𝑊 ) = ( ♯ ‘ 𝑊 ) )
4 3 2 wrdfd ( 𝜑𝑊 : ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ⟶ 𝑆 )
5 fzofi ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ∈ Fin
6 5 a1i ( 𝜑 → ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ∈ Fin )
7 4 6 1 fdmfifsupp ( 𝜑𝑊 finSupp 𝑍 )