[clean-list] What does the L mean in the expression: : CloudsVertVisibility = L [CloudsVV] | SkyClear

[metaperl]

I dont understand what the "L" means below. I'm guessing it is a type
constructor for CludsVertVisibility which takes one argument... Just like
"SkyClear" is a nullary type constructor.

// clouds and vertical visibility

:: CloudsVertVisibility = L [CloudsVV] | SkyClear

:: CloudsVV = {amount :: CloudAmount,visibility :: Int}

:: CloudAmount = Few | Scattered | Broken | Overcast
-- 
View this message in context: http://www.nabble.com/What-does-the-L-mean-in-the-expression%3A-%3A-CloudsVertVisibility-%3D-L--CloudsVV--%7C-SkyClear-tp19149990p19149990.html
Sent from the Clean mailing list archive at Nabble.com.