SWI-Prolog -- put_assoc/4

Documentation
- Reference manual
  - The SWI-Prolog library
    - library(assoc): Association lists
      - Modifying association lists
        
        put_assoc/4
        
        del_assoc/4
        
        del_min_assoc/4
        
        del_max_assoc/4
- Packages

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

Source

[det]put_assoc(+Key, +Assoc0, +Value, -Assoc)

Assoc is Assoc0, except that Key is associated with Value. This can be used to insert and change associations.