The issue is how does a machine determine which parenthesis shouldn't be there?
Consider the following code and adapt

my $string="one two one two";
my @ones=$string=~m/\bone\b/g;
my @twos=$string=~m/\btwo\b/g;
print scalar(@ones) ,"\t\"ones\"\n",scalar (@twos),"\t\"twos\"\n"; 
print "Equal numbers\n" if (scalar (@ones)== scalar (@twos));'
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You can flag that there are unmatched braces on a line, but a human may be needed to determine which is the incorrect brace. Hope this helps