open-stdin
| as-records
| print
;

Exception in thread "main" org.metafacture.flux.FluxParseException: Variable open-stdin not assigned.
        at org.metafacture.flux.parser.FlowBuilder.exp(FlowBuilder.java:604)
        at org.metafacture.flux.parser.FlowBuilder.flow(FlowBuilder.java:205)
        at org.metafacture.flux.parser.FlowBuilder.flux(FlowBuilder.java:122)
        at org.metafacture.flux.FluxCompiler.compileFlow(FluxCompiler.java:66)
        at org.metafacture.flux.FluxCompiler.compile(FluxCompiler.java:54)
        at org.metafacture.runner.Flux.main(Flux.java:87)

"" // as well as "stdIn"
| open-stdin
| as-records
| print
;

Exception in thread "main" java.lang.IllegalArgumentException: Parameter not used. Must be null
        at org.metafacture.io.StdInOpener.process(StdInOpener.java:59)
        at org.metafacture.flux.parser.StringSender.process(StringSender.java:43)
        at org.metafacture.flux.parser.Flow.start(Flow.java:118)
        at org.metafacture.flux.parser.FluxProgramm.start(FluxProgramm.java:168)
        at org.metafacture.runner.Flux.main(Flux.java:87)

| open-stdin
| as-records
| print
;

Exception in thread "main" java.lang.NullPointerException
        at org.antlr.runtime.tree.BaseTreeAdaptor.isNil(BaseTreeAdaptor.java:70)
        at org.antlr.runtime.tree.CommonTreeNodeStream.nextElement(CommonTreeNodeStream.java:93)
        at org.antlr.runtime.misc.LookaheadStream.fill(LookaheadStream.java:94)
        at org.antlr.runtime.misc.LookaheadStream.sync(LookaheadStream.java:88)
        at org.antlr.runtime.misc.LookaheadStream.LT(LookaheadStream.java:119)
        at org.antlr.runtime.tree.CommonTreeNodeStream.LA(CommonTreeNodeStream.java:116)
        at org.metafacture.flux.parser.FlowBuilder.varDefs(FlowBuilder.java:277)
        at org.metafacture.flux.parser.FlowBuilder.flux(FlowBuilder.java:105)
        at org.metafacture.flux.FluxCompiler.compileFlow(FluxCompiler.java:66)
        at org.metafacture.flux.FluxCompiler.compile(FluxCompiler.java:54)
        at org.metafacture.runner.Flux.main(Flux.java:87)