idlwave-indent-to-open-paren

idlwave-indent-to-open-paren is a variable defined in `idlwave.el'.
Its value is

t

Documentation:
Non-nil means, indent continuation lines to innermost open parenthesis.
This indentation occurs even if otherwise disallowed by
`idlwave-max-extra-continuation-indent'. Matching parens and the
interleaving args are lined up. Example:

x = function_a(function_b(function_c( a, b, [1,2,3, $
4,5,6 $
], $
c, d $
)))

When this variable is nil, paren alignment may still occur, based on
the value of `idlwave-max-extra-continuation-indent', which, if zero,
would yield:

x = function_a(function_b(function_c( a, b, [1,2,3, $
4,5,6 $
], $
c, d $
)))

You can customize this variable.