Change Constant(undef) error to something meaningful

Look at these errors:

$ perl5.16.0 -e 'use overload; BEGIN{overload::constant q => sub{}; } "aaa"'
Constant(q): Call to &{$^H{q}} did not return a defined value at -e line 1, near "} "aaa""
Execution of -e aborted due to compilation errors.

$ perl5.16.0 -e 'BEGIN{++$_ for @INC{<charnames.pm _charnames.pm>}} "\N{a}"'
Constant(\N{a}) unknown at -e line 1, within string
Execution of -e aborted due to compilation errors.

$ perl5.16.0 -e 'use overload; BEGIN{overload::constant q => sub{}; } tr"aaa""'
Constant(tr): Call to &{$^H{q}} did not return a defined value at -e line 1, within string
Execution of -e aborted due to compilation errors.

The (q) and (tr) might seem a bit odd, but are not completely meaning-
less.  They match the third argument passed to the overload handler.
Now look at this:

$ perl5.16.0 -e 'use overload; BEGIN{overload::constant integer => sub{}; } 123'
Constant(undef): Call to &{$^H{integer}} did not return a defined value at -e line 1, at end of line
Execution of -e aborted due to compilation errors.

$ perl5.16.0 -e 'use overload; BEGIN{overload::constant float => sub{}; } 1.23'
Constant(undef): Call to &{$^H{float}} did not return a defined value at -e line 1, at end of line
Execution of -e aborted due to compilation errors.

$ perl5.16.0 -e 'use overload; BEGIN{overload::constant binary => sub{}; } 0x123'
Constant(undef): Call to &{$^H{binary}} did not return a defined value at -e line 1, at end of line
Execution of -e aborted due to compilation errors.

That Constant(undef) is not helpful.  This commit changes it to show
the number itself, making these cases similar to \N{}.

1 files changed, 6 insertions, 6 deletions

diff --git a/t/lib/croak/toke b/t/lib/croak/toke
index cd1fc2023c..329e12ce66 100644
--- a/t/lib/croak/toke
+++ b/t/lib/croak/toke
@@ -33,7 +33,7 @@ use overload;
 BEGIN { overload::constant integer => sub {}; undef *^H }
 1
 EXPECT
-Constant(undef) unknown at - line 3, at end of line
+Constant(1) unknown at - line 3, at end of line
 Execution of - aborted due to compilation errors.
 ########
 # NAME Float constant overloading returning undef
@@ -41,7 +41,7 @@ use overload;
 BEGIN { overload::constant float => sub {}; undef *^H }
 1.1
 EXPECT
-Constant(undef) unknown at - line 3, at end of line
+Constant(1.1) unknown at - line 3, at end of line
 Execution of - aborted due to compilation errors.
 ########
 # NAME Binary constant overloading returning undef
@@ -49,7 +49,7 @@ use overload;
 BEGIN { overload::constant binary => sub {}; undef *^H }
 0x1
 EXPECT
-Constant(undef) unknown at - line 3, at end of line
+Constant(0x1) unknown at - line 3, at end of line
 Execution of - aborted due to compilation errors.
 ########
 # NAME String constant overloading returning undef
@@ -84,7 +84,7 @@ use overload;
 BEGIN { overload::constant integer => sub {} }
 1
 EXPECT
-Constant(undef): Call to &{$^H{integer}} did not return a defined value at - line 3, at end of line
+Constant(1): Call to &{$^H{integer}} did not return a defined value at - line 3, at end of line
 Execution of - aborted due to compilation errors.
 ########
 # NAME Float constant overloading returning undef
@@ -92,7 +92,7 @@ use overload;
 BEGIN { overload::constant float => sub {} }
 1.1
 EXPECT
-Constant(undef): Call to &{$^H{float}} did not return a defined value at - line 3, at end of line
+Constant(1.1): Call to &{$^H{float}} did not return a defined value at - line 3, at end of line
 Execution of - aborted due to compilation errors.
 ########
 # NAME Binary constant overloading returning undef
@@ -100,7 +100,7 @@ use overload;
 BEGIN { overload::constant binary => sub {} }
 0x1
 EXPECT
-Constant(undef): Call to &{$^H{binary}} did not return a defined value at - line 3, at end of line
+Constant(0x1): Call to &{$^H{binary}} did not return a defined value at - line 3, at end of line
 Execution of - aborted due to compilation errors.
 ########
 # NAME String constant overloading returning undef