ref: c4f1e9166e14cd17667438f6af69460ad1d35ecf
dir: /test/t.coerce3/
{
print index(1e0, $1)
print substr(123456789, 1e0, 3)
print 123456789 ~ 1e0, 1e0 ~ 123456789
print 1e0 in x
print 1e0 23 456
print 123456789 ~ 1e0, 1e0 ~ 123456789, 123456789 ~ "abc"
}