layerの文字列操作

layer = thisComp.layer(6).name;
compName = thisComp.name;
cp = "_compo_ ";
ext = layer.slice(-4);
duration = layer.match(/\d{4}-\d{4}/);
version = layer.match(/v\d{2}|v\d{3}/);
dot = ".";
compNameDot = compName.concat(dot);
compNameDot.concat(version);