## S4 method for signature 'SpatVector'
is.valid(x, messages=FALSE)

w <- vect("POLYGON ((0 -5, 10 0, 10 -10, 0 -5))")
is.valid(w)

w <- vect("POLYGON ((0 -5, 10 0, 10 -10, 4 -2, 0 -5))")
is.valid(w)
is.valid(w, TRUE)

plot(w)
points(cbind(4.54, -2.72), cex=2, col="red")

# invalid polygon
#w <- vect("POLYGON ((0 -5, 10 0, 10 -10, 4 -2))")
#is.valid(w)