An OpenSCAD script to get a partial rotate_extrude

rotate_extrude_angle.scad

rotate_extrude_angle(90) translate([10, 0, 0]) circle(5);

// A workaround until the new "angle" parameter of rotate_extrude arrives to the public release
module rotate_extrude_angle(angle, r=9999) {
	intersection() {
		rotate_extrude() children(0);
		translate([0, 0, -r/2]) linear_extrude(r) circle_sector(r, 0, angle); // see below
	}
}

module circle_sector(r, from, to) {
	intersection() {
		circle(r);
		if (abs(to - from) < 360) { // Less than 360?? then substract to get sector
			to = to + ((to <= from) ? 360 : 0); // ensure (from < to)
			angles = concat([for(angle = [from:$fa:to-0.1]) angle], to);
			polygon(concat([[0, 0]], [for (angle = angles) [(0.1+r)*cos(angle),(0.1+r)*sin(angle)]]));
		}
	}
}