//ww:run-exit 95
// Migrated from 775_io_vtable_run row branched_readers.
package main;
import io;
fn r1(s: io.stream, buf: []u8) (size | io.eof | io.error) = {
    return 1: size;
};
fn r2(s: io.stream, buf: []u8) (size | io.eof | io.error) = {
    return 2: size;
};
export fn main() i32 = {
    let vt1: io.vtable;
    let vt2: io.vtable;
    vt1.reader = (&r1): *io.reader;
    vt2.reader = (&r2): *io.reader;
    let buf: [4]u8;
    let bs: []u8 = buf[0:4];
    let a = io.read(&vt1, bs);
    let b = io.read(&vt2, bs);
    let asz: size = 0;
    let bsz: size = 0;
    if (a is size) { asz = a as size; };
    if (b is size) { bsz = b as size; };
    if (asz == 1: size && bsz == 2: size) { return 95; };
    return 99;
};