// Check the output.
#rgb(0.0, 0.3, 0.7)

// Alpha channel.
#rgb(1.0, 0.0, 0.0, 0.5)

// Warning: 2:6-2:9 should be between 0.0 and 1.0
// Warning: 1:11-1:15 should be between 0.0 and 1.0
#rgb(-30, 15.5, 0.5)

// Error: 6-10 missing argument: blue component
#rgb(0, 1)

// Error: 3:6-3:6 missing argument: red component
// Error: 2:6-2:6 missing argument: green component
// Error: 1:6-1:6 missing argument: blue component
#rgb()