perl -le 'use strict; my $foo = 1; $foo ? \&{print "foo"} : \&{ print 
+"bar"};'
foo
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Inside a ternary ?: the expressions are evaluated - and \& { } constructs a code ref block which gets evaluated at runtime, to get at the name of the symbol table entry CODE slot from which a reference is taken.

perl -MO=Concise,-exec -le '$foo = 1; $foo ? \&{print "foo"} : \&{ pri
+nt "bar"};'
1  <0> enter 
2  <;> nextstate(main 1 -e:1) v
3  <$> const[IV 1] s
4  <#> gvsv[*foo] s
5  <2> sassign vKS/2
6  <;> nextstate(main 3 -e:1) v
7  <#> gvsv[*foo] s
8  <|> cond_expr(other->9) vK/1
9      <0> pushmark sRM
a      <0> pushmark s
b      <$> const[PV "foo"] s
c      <@> print sK
d      <1> rv2cv[t3] lKRM/AMPER,33   <---- here
e      <1> refgen vK/1
           goto f
g  <0> pushmark sRM
h  <0> pushmark s
i  <$> const[PV "bar"] s
j  <@> print sK
k  <1> rv2cv[t4] lKRM/AMPER,33 <---- and here
l  <1> refgen vK/1
f  <@> leave[1 ref] vKP/REFC
-e syntax OK
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perl -le 'use strict; my $foo = \&{ print "bar"}; $foo'
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</update>

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}