def read.opened

ezx@1.11.0.0 · src/io/file.bend:83

import Base

83# what an opened file holds, or nothing when it would not open
84def read.opened(res: Result<&1, &1, U32 & String, File>) -> IO(Maybe<&2, String>):
85  match res:
86    case Fail{_e}:
87      IO.pure(Maybe<&2, String>, None{})
88    case Done{file}:
89      do IO<Maybe<&2, String>>:
90        got : File & Result<&1, &1, U32 & String, U32> <- File.size(file)
91        text : String <- read.sized(got)
92        return Some{text}