Eelco Dolstra
59b94ee18a
print a nice backtrace of the stack, rather than vomiting a gigantic
(and useless) aterm on the screen. Example:
error: while evaluating file `.../pkgs/system/test.nix':
while evaluating attribute `subversion' at `.../pkgs/system/all-packages-generic.nix', line 533:
while evaluating function at `.../pkgs/applications/version-management/subversion/default.nix', line 1:
assertion failed at `.../pkgs/applications/version-management/subversion/default.nix', line 13
Since the Nix expression language is lazy, the trace may be
misleading. The purpose is to provide a hint as to the location of
the problem.
*** Nix *** For installation and usage instructions, please read the manual, which can be found in docs/manual/manual.html, and additionally at the Nix website at <http://www.cs.uu.nl/groups/ST/Trace/NixDeploymentSystem>.