Maybe a wrapper method $safecall is what you need, you can put all runtime checks needed in there.

Please note that arguments are optional and need to be passed as array_refs in order to be distinguished from methodnames.

$\="\n"; sub safecall{ db(@_); my $obj=shift; # TODO check object/class my ($meth,$a_args); while (@_){ $meth=shift; # TODO check method $a_args= (ref $_[0] eq "ARRAY" ? shift : []); $obj=$obj->$meth(@$a_args); # TODO check ret +urned obj } print "-"x20; return $obj; }; my $safecall=\&safecall; my $obj={}; bless $obj, CLASS; #- USAGE/INTERFACE - $obj->$safecall( "meth1" ); $obj->$safecall( meth1=> meth2=> [3,4,5] ); $obj->$safecall( qw(meth1 meth2) ); $obj->$safecall( meth1=>[1,2,3] , meth2=> [3,4,5] ); $obj->$safecall( meth1=>[1,2,3] ) -> meth2(3,4,5); # still possible safecall($obj, meth1=>[1,2,3] , meth2=> [3,4,5]); # fuctional appr +oach package CLASS; sub meth1 { my $self=shift; print "call meth1 with (@_)"; return $self; } sub meth2 { my $self=shift; print "call meth2 with (@_)"; return $self; }

OUTPUT:

call meth1 with () ---------- call meth1 with () call meth2 with (3 4 5) ---------- call meth1 with () call meth2 with () ---------- call meth1 with (1 2 3) call meth2 with (3 4 5) ---------- call meth1 with (1 2 3) ---------- call meth2 with (3 4 5)

Cheers Rolf

UPDATE: added functional approach.


In reply to Re: Error handling in chained method calls by LanX
in thread Error handling in chained method calls by szabgab

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.