'lookAhead' is exactly what I needed:

try $ array_element >>= \ae -> lookAhead (reservedOp "(") >> return ae

Many thanks,
Paul

Maybe you're looking for 'lookAhead'?

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//Stephan

--

Früher hieß es ja: Ich denke, also bin ich.
Heute weiß man: Es geht auch so.

 - Dieter Nuhr