String.to_upper: def of Base
Import: import Base
Lines 2227-2232 of Base/base.bend: https://jend.leeeet.dev/read.txt?path=Base/base.bend&start_line=2227&end_line=2232

import Base

def String.to_upper(s: String) -> String:
  match s:
    case SNil{}:
      SNil{}
    case SCon{h, t}:
      SCon{Char.to_upper(h), String.to_upper(t)}

Uses (2):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Char.to_upper
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String