Short version:

I'm interested to interactively deactivate a bunch debugger commands like { - at least temporarily.

Is there a recommended way, except patching perl5db.pl and pointing the environment to the patch?

Long version

My motivation is to use the debugger as a REPL to automatically print evaluated values.

But many perldebug#Debugger-Commands only make sense when used while debugging

  DB<50> h
List/search source lines:               Control script execution:
  l [ln|sub]  List source code            T           Stack trace
  - or .      List previous/current line  s [expr]    Single step [in 
+expr]
  v [line]    View around line            n [expr]    Next, steps over
+ subs

... yadda yadda
[download]

and such pure debugger commands like { and [ at first position are interfering with Perl's syntax, such that

  DB<1> { a => 1 }         # not an anonym hash
  DB<2> {
pre-debugger commands:
        { -- a => 1 }
  DB<2>
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So my idea was using aliases to deactivate them, it works but runs into a a missing quotemeta bug in the debugger

  DB<1> = { ;{
Unescaped left brace in regex is deprecated, passed through in regex; 
+marked by <-- HERE in m/s\a{ <-- HERE \a(.*)\a$/ at C:/Perl_524/lib/p
+erl5db.pl line 3826.
 at C:/Perl_524/lib/perl5db.pl line 3826.
        DB::Obj::_handle_equal_sign_command(DB::Obj=HASH(0x24de098)) c
+alled at C:/Perl_524/lib/perl5db.pl line 2881
        DB::DB called at -e line 1
{       = ;{
  DB<2> { a => 1 }

  DB<3> {
Missing right curly or square bracket at (eval 14)[C:/Perl_524/lib/per
+l5db.pl:737] line 3, at end of line
syntax error at (eval 14)[C:/Perl_524/lib/perl5db.pl:737] line 3, at E
+OF

  DB<3>
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My bigger concern is that defining dozens of "pseudo aliases" makes listing the user defined aliases with = unreadable.

  DB<6> h =
= [alias value]    Define a command alias, or list current aliases.
  DB<7>
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FWIW: I could use PadWalker to access the lexical hashes defining/dispatching the commands, but this is even messier.