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Sometimes, understanding the derivations is difficult, because they
are serialized to fit in one line. For instance, the example taken
from the NEWS file:
%token ID
%%
s: a ID
a: expr
expr: expr ID ',' | "expr"
gave
First example expr • ID ',' ID $end
Shift derivation $accept → [ s → [ a → [ expr → [ expr • ID ',' ] ] ID ] $end ]
Second example expr • ID $end
Reduce derivation $accept → [ s → [ a → [ expr • ] ID ] $end ]
Printing as trees, it gives:
First example expr • ID ',' ID $end
Shift derivation
$accept
↳ s $end
↳ a ID
↳ expr
↳ expr • ID ','
Second example expr • ID $end
Reduce derivation
$accept
↳ s $end
↳ a ID
↳ expr •
* src/glyphs.h, src/glyphs.c (down_arrow, empty, derivation_separator):
New.
* src/derivation.c (derivation_print, derivation_print_impl): Rename
as...
(derivation_print_flat, derivation_print_flat_impl): These.
(fputs_if, derivation_depth, derivation_width, derivation_print_tree)
(derivation_print_tree_impl, derivation_print): New.
* src/counterexample.c (print_counterexample): Adjust.
* tests/conflicts.at, tests/counterexample.at, tests/diagnostics.at,
* tests/report.at: Adjust.