System.Process.readProcess: incorrect documentation of return value
Originally reported at Haskell Platform bug tracker:
The System.Process docs here:
describes the return value as:
returns either the output string, or, in the case of non-zero exit status, an error code, and any output.
and the given example output is:
Right "Thu Feb 7 10:03:39 PST 2008\n"
This suggests that the return value looks like:
IO (Either ? String)
But the return type is shown (in that same documentation, and in ghci 6.12.3) as IO String, and my own experimentation shows no "Right" being returned in the case of a successful operation - instead I get only the String containing the program output, not wrapped.
Perhaps this is historic.
Trac metadata
Trac field | Value |
---|---|
Version | 6.12.3 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | libraries/process |
Test case | |
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