Don't throw an exception when global.Substance is already defined, only log a warning.
Don't throw an exception when global.Substance is already defined, only log a warning.
substance/substance,andene/substance,michael/substance-1,jacwright/substance,jacwright/substance,andene/substance,stencila/substance,michael/substance-1,podviaznikov/substance,substance/substance,podviaznikov/substance