Date.Date.start_of_month: def of bend-time-lib@0.4.0.1
Import: import bend-time-lib@0.4.0.1/date.bend as Date
Lines 153-156 of bend-time-lib@0.4.0.1/date.bend: https://jend.leeeet.dev/read.txt?path=bend-time-lib@0.4.0.1/date.bend&start_line=153&end_line=156

import Base

def Date.start_of_month(date: Date) -> Date:
  match date:
    case Date{y, m, _}:
      Date{y, m, 1}

Uses (1):
  https://jend.leeeet.dev/definition.txt?path=bend-time-lib@0.4.0.1/date.bend&name=Date