cannot construct a PeUnit, no constructor in IDL

Question

When using client side projection utility I was getting this error "cannot construct a PeUnit, no constructor in IDL". Google gave no results so I thought I'd log the solution here:

This causes the issue

var extprj = projection.project(new Extent(ext), this.map.spatialReference); // project extthis.map.setExtent(extprj);

The solution is to create a new extent/clone it to pass into the projection

var extprj = projection.project(new Extent(ext),  new SpatialReference(this.map.spatialReference.wkid)); // project extthis.map.setExtent(extprj);If you don't any time attempts are made to clone the map spatial reference it causes errors. I was using an older version of the API (3.24) so may have been resolved

DavidWilton · Accepted Answer

Solution is to clone the map spatial reference:

var extprj = projection.project(new Extent(ext),  new SpatialReference(this.map.spatialReference.wkid)); // project extthis.map.setExtent(extprj);