As soon as I add a hand-written nabl-constraint like the following, all my example files fail analysis…

nabl-constraint(|ctx): Decl(_,n) -> <fail>
  where lookup := <nabl-lookup-lexical-parent(|ctx)> n
      ; <task-create-error-on-success(|ctx, lookup, $[Shadowing (duplicate) definition])> n

I tried right-clicking on projects and selecting Spoofax > Reload analysis data. It doesn’t help.
How do I work around this?

---

Stratego stack trace:

Internal error evaluating editor-analyze (InterpreterException; see error log)
rewriting failed, trace:
	editor_analyze_0_0
	analysis_default_editor_0_0
	analysis_single_default_interface_0_0
	analysis_single_default_3_1
	analysis_single_default_4_1
	analysis_files_spoofax_4_2
	analysis_files_spoofax_5_2
	analysis_files_4_2
	analysis_files_no_builtins_6_2
	measure_time_2_0
	x_652
	map_1_0
	analysis_collect_1_2
	d_706
	preserve_annos_1_0
	origin_track_forced_1_0
	m_857
	nabl_siblings_0_4
	nabl_siblings_0_4
	nabl_collect_1_4
	preserve_annos_1_0
	origin_track_forced_1_0
	m_857
	nabl_siblings_0_4
	nabl_collect_1_4
	preserve_annos_1_0
	origin_track_forced_1_0
	m_857
	nabl_siblings_0_4
	nabl_siblings_0_4
	nabl_collect_1_4
	preserve_annos_1_0
	origin_track_forced_1_0
	m_857
	nabl_siblings_0_4
	nabl_siblings_0_4
	nabl_collect_1_4
	preserve_annos_1_0
	origin_track_forced_1_0
	m_857
	nabl_siblings_0_4
	nabl_siblings_0_4
	nabl_collect_1_4
	nabl_annotate_properties_0_4
	try_1_0
	nabl_constraint_0_4
	nabl_constraint_0_3
	nabl_constraint_0_1
	nabl_lookup_lexical_0_1
	nabl_uri_0_0
	fetch_elem_1_0
	nabl_collect_one_resolved_def_0_0
	insert_results_or_delay_0_0
	task_delay_0_0
	task_api_delay_0_1

Part of the Java stacktrace:

Caused by: java.lang.RuntimeException: Cannot delay task while no task evaluation is in progress.
	at org.metaborg.runtime.task.primitives.task_api_delay_0_1.call(task_api_delay_0_1.java:26)
	at org.spoofax.interpreter.stratego.PrimT.eval(PrimT.java:63)
	at org.spoofax.interpreter.stratego.Strategy.evaluate(Strategy.java:76)
	at org.spoofax.interpreter.stratego.SDefT.evaluate(SDefT.java:213)
	at org.strategoxt.lang.InteropStrategy.invokeDynamic(InteropStrategy.java:57)

Submitted by Jeff Smits on 11 June 2015 at 22:06

I’m not sure if you can do nabl-lookup-lexical-parent during collection time, but I think this is ok.

I have tasks using nabl-lookup-lexical, maybe it helps you to look at it: https://github.com/metaborg/relations/blob/master/relations/trans/lib/nabl-ext.str

This error indicates that you are trying to use task results outside of task evaluation. I’m not entirely sure what nabl-lookup-lexical-parent does, but it seems to get a URI, but this requires resolving a use to a def with nabl_collect_one_resolved_def, and then fails because this task has not been computed yet, and task evaluation has not been started yet. Maybe n or its annotations have a use in them?

Ok that makes sense. I don’t want to resolve names at that point. I just want to get back a task that will do the lookup later. What do I need to call for that?

I have code that checks for duplicate names in separate namespaces - which is quite similar to looking wether you shadow a name in an above namespace.

On definitions you can just use the non-task strategies on names and uri’s: and find the name and namespace you want to do something with.

Then in the end you can use tasks to do the lookup:

role-defs := <_nabl-lookup-lexical(|ctx, conflict-ns)> a-name;
				<_task-create-error-on-success(|ctx, role-defs, ["Conflicting ", <_pp-ns>ns, " and ", <_pp-ns>conflict-ns, " ", a-name, " in ", <_pp-ns>parent-ns, " ", parent])> a-name

Full code:

Use:

rules // check if there are no name collisions in attributes, roles, inverses and shortcuts
	
	ns-conflict-error = ![
		[NablNsAttribute(), NablNsRole(), NablNsInverse(), NablNsShortcut()]
	]

Lib:

rules // api for conflicting nses error messages
	
	nabl-constraint(|ctx):	a -> <fail>
		where
			<is-string>a;                     //on all strings
			name := <nabl-get-name>a;         //that have an nabl name
			<not(_nabl-has-reference)>name;    //and this name is a def
			uri := <_nabl-uri> name;
			ns	:= <_nabl-uri-namespace> uri;
			nses := <ns-conflict-error;filter(fetch(?ns));Hd>ns //get the list of nses that this ns is in (where-fail if there is no such list)
		with
			<name-nses-conflict(|ctx, nses)>name

	name-nses-conflict(|ctx,nses): a-name -> <id>
		with
			<map(name-ns-conflict(|ctx, a-name))>nses

	name-ns-conflict(|ctx, a-name): conflict-ns -> <id>
		with
			uri := <_nabl-uri> a-name;
			ns	:= <_nabl-uri-namespace> uri;
			if <not(eq)> (conflict-ns, ns) then
				uri':= <_nabl-uri-parent> uri;
				parent:= <_nabl-uri-name> uri';
				parent-ns := <_nabl-uri-namespace> uri';
				role-defs := <_nabl-lookup-lexical(|ctx, conflict-ns)> a-name;
				<_task-create-error-on-success(|ctx, role-defs, ["Conflicting ", <_pp-ns>ns, " and ", <_pp-ns>conflict-ns, " ", a-name, " in ", <_pp-ns>parent-ns, " ", parent])> a-name
			end

	ns-conflict-error = fail // interface implemented by language
	
	nabl-get-name = fail // generated by nabl

@gohla was right that I’m using nabl-lookup on a reference, not a definition. It’s been a while since I wrote these rules manually and I thought I had to do an nabl-lookup, but I didn’t. The task inside the Use annotation was enough.
So the piece of Stratego causing all this was:

nabl-constraint(|ctx) = ?term; one(?i@Implicit())
  ; lookup := <nabl-lookup-lexical(|ctx)> i
  ; <task-create-error-on-multiple(|ctx, lookup, $[Multiple graphs found, specify associated graph])> term
  ; fail

And I should have used:

nabl-constraint(|ctx) = ?term; one(?i@Implicit())
  ; <has-annotation(?Use(lookup))> i
  ; <task-create-error-on-multiple(|ctx, lookup, $[Multiple graphs found, specify associated graph])> term
  ; fail

The runtime exception is rather awful though. Can the library or runtime be patched, so you get something that at least hints at what you’re doing wrong?