29 lines
502 B
Plaintext
29 lines
502 B
Plaintext
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###
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### concatenate2-continuation
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###
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## Chapter 8 section 8.1
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sub concatenate2 {
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my ($A, $B) = @_;
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my $p;
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$p = parser {
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my ($input, $continuation) = @_;
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my ($aval, $bval);
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my $BC = parser {
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my ($newinput) = @_;
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return unless ($bval) = $B->($newinput, $continuation);
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};
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$N{$BC} = "$N{$B} $N{$continuation}";
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if (($aval) = $A->($input, $BC)) {
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return ([$aval, $bval]);
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} else {
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return;
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}
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};
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$N{$p} = "$N{$A} $N{$B}";
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return $p;
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}
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