Missing brackets when printing a function with iterated sublist access

[zickgraf]

Observed behaviour

gap> Display( x -> ([ 1 ]{[ 1 ]}){[ 1 ]} );
function ( x )
    return [ 1 ]{[ 1 ]}{[ 1 ]};
end

Expected behaviour

gap> Display( x -> ([ 1 ]{[ 1 ]}){[ 1 ]} );
function ( x )
    return ([ 1 ]{[ 1 ]}){[ 1 ]};
end

The brackets are important because [ 1 ]{[ 1 ]}{[ 1 ]} is interpreted as a submatrix access (which seems to be undocumented).

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[fingolfin]

I agree this is a bug.

The behaviour of [ 1 ]{[ 1 ]}{[ 1 ]} is documented here.

[fingolfin]

I think fixing this may be quite tricky. At the same time, it doesn't seem very important -- AFAIK we don't make any promises that functions can be round tripped by parsing their printed version (and indeed, in general this is not possible due to closures). I realize it may be important to you, all I want to convey here is that I wouldn't hold my breath for this to be fixed.

[zickgraf]

The behaviour of [ 1 ]{[ 1 ]}{[ 1 ]} is documented here.

Thanks for the hint! I couldn't find it previously and have created #5114.

I think fixing this may be quite tricky.

I gave this a shot in #5116.