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doc: factor ifnottex/iftex examples

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* doc/bison.texi: Factor the common bits out of ifnottex/iftex.
This commit is contained in:
Akim Demaille
2020-07-28 07:40:45 +02:00
parent fa390dc311
commit e63f22703e
1 changed files with 4 additions and 15 deletions
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doc/bison.texi
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@@ -9973,13 +9973,13 @@ maybeword:
Bison generates the following counterexamples: Bison generates the following counterexamples:
@ifnottex
@example @example
@group @group
$ @kbd{bison -Wcex sequence.y} $ @kbd{bison -Wcex sequence.y}
sequence.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}] sequence.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
sequence.y: @dwarning{warning}: 2 reduce/reduce conflicts [@dwarning{-Wconflicts-rr}] sequence.y: @dwarning{warning}: 2 reduce/reduce conflicts [@dwarning{-Wconflicts-rr}]
@end group @end group
@ifnottex
@group @group
sequence.y: @dwarning{warning}: shift/reduce conflict on token "word" [@dwarning{-Wcounterexamples}] sequence.y: @dwarning{warning}: shift/reduce conflict on token "word" [@dwarning{-Wcounterexamples}]
Example: @red{•} @green{"word"} Example: @red{•} @green{"word"}
@@ -10024,15 +10024,8 @@ sequence.y:8.3-45: @dwarning{warning}: rule useless in parser due to conflicts [
8 | @dwarning{%empty @{ printf ("empty maybeword\n"); @}} 8 | @dwarning{%empty @{ printf ("empty maybeword\n"); @}}
| @dwarning{^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~} | @dwarning{^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
@end group @end group
@end example
@end ifnottex @end ifnottex
@iftex @iftex
@example
@group
$ @kbd{bison -Wcex sequence.y}
sequence.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
sequence.y: @dwarning{warning}: 2 reduce/reduce conflicts [@dwarning{-Wconflicts-rr}]
@end group
@group @group
sequence.y: @dwarning{warning}: shift/reduce conflict on token "word" [@dwarning{-Wcounterexamples}] sequence.y: @dwarning{warning}: shift/reduce conflict on token "word" [@dwarning{-Wcounterexamples}]
Example: @red{•} @green{"word"} Example: @red{•} @green{"word"}
@@ -10077,8 +10070,8 @@ sequence.y:8.3-45: @dwarning{warning}: rule useless in parser due to conflicts [
8 | @dwarning{%empty @{ printf ("empty maybeword\n"); @}} 8 | @dwarning{%empty @{ printf ("empty maybeword\n"); @}}
| @dwarning{^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~} | @dwarning{^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
@end group @end group
@end example
@end iftex @end iftex
@end example
Each of these three conflicts, again, prove that the grammar is ambiguous. Each of these three conflicts, again, prove that the grammar is ambiguous.
For instance, the second conflict (the reduce/reduce one) shows that the For instance, the second conflict (the reduce/reduce one) shows that the
@@ -10103,10 +10096,10 @@ expr: %empty | expr ID ','
@command{bison} reports: @command{bison} reports:
@ifnottex
@example @example
ids.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}] ids.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
ids.y: @dwarning{warning}: shift/reduce conflict on token ID [@dwarning{-Wcounterexamples}] ids.y: @dwarning{warning}: shift/reduce conflict on token ID [@dwarning{-Wcounterexamples}]
@ifnottex
@group @group
First example: @purple{expr} @red{•} @purple{ID ','} @green{ID} @yellow{$end} First example: @purple{expr} @red{•} @purple{ID ','} @green{ID} @yellow{$end}
Shift derivation Shift derivation
@@ -10127,12 +10120,8 @@ ids.y:4.4-7: @dwarning{warning}: rule useless in parser due to conflicts [@dwarn
4 | a: expr 4 | a: expr
| ^~~~ | ^~~~
@end group @end group
@end example
@end ifnottex @end ifnottex
@iftex @iftex
@example
ids.y: @dwarning{warning}: 1 shift/reduce conflict [@dwarning{-Wconflicts-sr}]
ids.y: @dwarning{warning}: shift/reduce conflict on token ID [@dwarning{-Wcounterexamples}]
@group @group
First example: @purple{expr} @red{•} @purple{ID ','} @green{ID} @yellow{$end} First example: @purple{expr} @red{•} @purple{ID ','} @green{ID} @yellow{$end}
Shift derivation Shift derivation
@@ -10153,8 +10142,8 @@ ids.y:4.4-7: @dwarning{warning}: rule useless in parser due to conflicts [@dwarn
4 | a: expr 4 | a: expr
| ^~~~ | ^~~~
@end group @end group
@end example
@end iftex @end iftex
@end example
This conflict is caused by the parser not having enough information to know This conflict is caused by the parser not having enough information to know
the difference between these two examples. The parser would need an the difference between these two examples. The parser would need an