Js_of_ocaml_compiler.Source_maptype mapping = map listtype t = {version : int; | 
file : string; | 
sourceroot : string option; | 
mutable sources : string list; | 
mutable sources_content : string option list option; | 
mutable names : string list; | 
mutable mappings : mapping; | 
}val mapping_of_string : string -> mappingval string_of_mapping : mapping -> stringval empty : t