Re: [Caml-list] Puzzled by Scanf.Scanning.in_channel

[Gabriel Scherer <gabriel.scherer@gmail.com>]

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You should use bscanf:

# Scanf.fscanf;;
- : in_channel -> ('a, 'b, 'c, 'd) Scanf.scanner = <fun>
# Scanf.bscanf;;
- : Scanf.Scanning.in_channel -> ('a, 'b, 'c, 'd) Scanf.scanner = <fun>


On Mon, Jun 4, 2012 at 8:59 PM, Diego Olivier Fernandez Pons <
dofp.ocaml@gmail.com> wrote:

>    Caml-List,
>
> When I try to use Scanf.fscanf with an input channel created with
> Scanf.Scanning.from_string the type checker complains
>
>    let s = Scanf.Scanning.from_string "3" in Scanf.fscanf s "%i" (fun x ->
> x);;
>
>    Characters 55-56:
>    Error: This expression has type Scanf.Scanning.in_channel
>       but an expression was expected of type in_channel
>
> Which confuses me as from the manual I understood this should have worked.
>
>    val from_string : string -> in_channel
>
>    Scanning.from_string s returns a formatted input channel which
> reads from the given string. Reading starts from the first character
> in the string. The end-of-input condition is set when the end of the
> string is reached.
>
> Could anyone explain how is the proper way to generate a input channel
> from a string ? Its for testing a program that will use stdin in
> production.
>
>        Diego Olivier
>
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