SWI-Prolog -- min_assoc/3

Documentation
- Reference manual
  - The SWI-Prolog library
    - library(assoc): Association lists
      - Querying association lists
        
        get_assoc/3
        
        get_assoc/5
        
        max_assoc/3
        
        min_assoc/3
        
        gen_assoc/3
- Packages

Availability::- use_module(library(assoc)).(can be autoloaded)

Source

[semidet]min_assoc(+Assoc, -Key, -Value)

True if Key-Value is in assoc and Key is the smallest key.