# Advanced Functional Programming with Elixir: Problem Running Code Example

**URL:** <https://forum.devtalk.com/t/advanced-functional-programming-with-elixir-problem-running-code-example/216820>\
**Category:** PragProg Customers\
**Tags:** book-advanced-functional-programming-with-elixir, errata\
**Created:** [30 September 2025 16:03 UTC](https://forum.devtalk.com/t/advanced-functional-programming-with-elixir-problem-running-code-example/216820 "2025-09-30T16:03:56Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![luistavera](https://forum.devtalk.com/user_avatar/forum.devtalk.com/luistavera/32/8117_2.png) [@luistavera](https://forum.devtalk.com/u/luistavera)\
**Post date:** [12 July 2026 16:09 UTC](https://forum.devtalk.com/t/advanced-functional-programming-with-elixir-problem-running-code-example/216820/2 "2026-07-12T16:09:22Z")

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Hi

I am running into the same issue. I think this is an error in the book since the Predicate expects a function with arity 1. The following works:  
def elegible?(%Patron{} = patron, % **MODULE** {} = ride) do  
te = fn patron → tall\_enough?(patron, ride) end  
oe = fn patron → old\_enough?(patron, ride) end  
p\_all([te, oe]).(patron)  
end  
Cheers

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