-- Calling a map-returning user function before using map builtins.
--
-- Common pitfall: writing `tg=mkmap` binds the function reference
-- itself (F M t n), not its result. Then `mget tg "a"` is a verifier
-- error (ILO-T013 'mget' expects a map, got F M t n). The fix is to
-- call the function with `mkmap()` so `tg` holds the map.
--
-- This example demonstrates the correct shape across mget, mset,
-- mhas, mdel and mvals, all chained off a user-fn that returns a map.
mkmap>M t n;m=mset mmap "a" 1;mset m "b" 2
look>n
tg=mkmap()
v=mget!! tg "a"
v
upd>L n
tg=mkmap()
tg=mset tg "c" 3
mvals tg
dropof>b
tg=mkmap()
tg=mdel tg "a"
mhas tg "a"
-- run: look
-- out: 1
-- run: upd
-- out: [1, 2, 3]
-- run: dropof
-- out: false