Usage of scalars

[noahboerger]

Scalars can currently not be used in Trevas in VTL expressions where constants / literals are allowed. As an example the following VTL code is failing

ds1 := simple_data;
my_scalar := 3;

ds_r := ds1[filter val = my_scalar];

e.g. for simple_data being the dataset

id_1	id_2	val
IDENTIFIER	IDENTIFIER	MEASURE
INTEGER	INTEGER	INTEGER
1	2	3
4	5	6

with the exception

Occured error

### Exception ``` fr.insee.vtl.engine.exceptions.UndefinedVariableException: undefined variable my_scalar at fr.insee.vtl.engine.visitors.expression.VarIdVisitor.visitVarID(VarIdVisitor.java:42) at fr.insee.vtl.engine.visitors.expression.VarIdVisitor.visitVarID(VarIdVisitor.java:23) at fr.insee.vtl.parser.VtlParser$VarIDContext.accept(VtlParser.java:9572) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.visitors.expression.ExpressionVisitor.visitVarID(ExpressionVisitor.java:106) at fr.insee.vtl.engine.visitors.expression.ExpressionVisitor.visitVarID(ExpressionVisitor.java:41) at fr.insee.vtl.parser.VtlParser$VarIDContext.accept(VtlParser.java:9572) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visitChildren(AbstractParseTreeVisitor.java:46) at fr.insee.vtl.parser.VtlBaseVisitor.visitVarIdExpr(VtlBaseVisitor.java:48) at fr.insee.vtl.parser.VtlParser$VarIdExprContext.accept(VtlParser.java:478) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.visitors.expression.ComparisonVisitor.visitComparisonExpr(ComparisonVisitor.java:142) at fr.insee.vtl.engine.visitors.expression.ComparisonVisitor.visitComparisonExpr(ComparisonVisitor.java:28) at fr.insee.vtl.parser.VtlParser$ComparisonExprContext.accept(VtlParser.java:586) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.visitors.expression.ExpressionVisitor.visitComparisonExpr(ExpressionVisitor.java:202) at fr.insee.vtl.engine.visitors.expression.ExpressionVisitor.visitComparisonExpr(ExpressionVisitor.java:41) at fr.insee.vtl.parser.VtlParser$ComparisonExprContext.accept(VtlParser.java:586) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.visitors.ClauseVisitor.visitFilterClause(ClauseVisitor.java:167) at fr.insee.vtl.engine.visitors.ClauseVisitor.visitFilterClause(ClauseVisitor.java:33) at fr.insee.vtl.parser.VtlParser$FilterClauseContext.accept(VtlParser.java:1743) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visitChildren(AbstractParseTreeVisitor.java:46) at fr.insee.vtl.parser.VtlBaseVisitor.visitDatasetClause(VtlBaseVisitor.java:230) at fr.insee.vtl.parser.VtlParser$DatasetClauseContext.accept(VtlParser.java:1494) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.visitors.expression.ExpressionVisitor.visitClauseExpr(ExpressionVisitor.java:357) at fr.insee.vtl.engine.visitors.expression.ExpressionVisitor.visitClauseExpr(ExpressionVisitor.java:41) at fr.insee.vtl.parser.VtlParser$ClauseExprContext.accept(VtlParser.java:683) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.visitors.AssignmentVisitor.visitAssignment(AssignmentVisitor.java:51) at fr.insee.vtl.engine.visitors.AssignmentVisitor.visitTemporaryAssignment(AssignmentVisitor.java:59) at fr.insee.vtl.parser.VtlParser$TemporaryAssignmentContext.accept(VtlParser.java:372) at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:18) at fr.insee.vtl.engine.VtlScriptEngine.evalStream(VtlScriptEngine.java:263) at fr.insee.vtl.engine.VtlScriptEngine.eval(VtlScriptEngine.java:282) at java.scripting/javax.script.AbstractScriptEngine.eval(AbstractScriptEngine.java:262) at fr.insee.trevas.jupyter.VtlKernel.eval(VtlKernel.java:305) at io.github.spencerpark.jupyter.kernel.BaseKernel.handleExecuteRequest(BaseKernel.java:334) at io.github.spencerpark.jupyter.channels.ShellChannel.lambda$bind$0(ShellChannel.java:64) at io.github.spencerpark.jupyter.channels.Loop.lambda$new$0(Loop.java:21) at io.github.spencerpark.jupyter.channels.Loop.run(Loop.java:78) ```

Such VTL statements are out of our point of view especially useful when the scalar value is set in the bindings outside of the script itself to parametrize the whole script execution.

Is that something that also needs to be adressed in the Task force Repo?

[NicoLaval]

Thanks @noahboerger. It's a Trevas issue, not a VTL issue. You are at the right place.