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cex: use usual routines for diagnostics about S/R conflicts

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See previous commit.  We go from

    input.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
    Shift/reduce conflict on token "⊕":
      Example              exp "+" exp • "⊕" exp
      Shift derivation
        exp
        ↳ exp "+" exp
                  ↳ exp • "⊕" exp

to

    input.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
    input.y: warning: shift/reduce conflict on token "⊕" [-Wcounterexamples]
      Example              exp "+" exp • "⊕" exp
      Shift derivation
        exp
        ↳ exp "+" exp
                  ↳ exp • "⊕" exp

with an hyperlink on -Wcounterexamples.

* src/counterexample.c (counterexample_report_shift_reduce):
Use complain.
* tests/counterexample.at, tests/diagnostics.at, tests/report.at:
Adjust.
This commit is contained in:
Akim Demaille
2020-07-19 19:34:34 +02:00
parent 9922f1f877
commit ea138cd1f1
5 changed files with 60 additions and 53 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
src/counterexample.c
View File

@@ -1248,8 +1248,15 @@ counterexample_report_shift_reduce (state_item_number itm1, state_item_number it
symbol_number next_sym,
FILE *out, const char *prefix)
{
fputs (prefix, out);
fprintf (out, _("Shift/reduce conflict on token %s:\n"), symbols[next_sym]->tag);
if (out == stderr)
complain (NULL, Wcounterexamples,
_("shift/reduce conflict on token %s"), symbols[next_sym]->tag);
else
{
fputs (prefix, out);
fprintf (out, _("shift/reduce conflict on token %s"), symbols[next_sym]->tag);
fprintf (out, "%s\n", _(":"));
}
// In the report, print the items.
if (*prefix || trace_flag & trace_cex)
{

6
tests/conflicts.at
View File

@@ -861,7 +861,7 @@ State 5
OP [reduce using rule 1 (exp)]
$default reduce using rule 1 (exp)
Shift/reduce conflict on token OP:
shift/reduce conflict on token OP:
1 exp: exp OP exp .
1 exp: exp . OP exp
Example exp OP exp . OP exp
@@ -1764,7 +1764,7 @@ State 4
reported_conflicts go to state 6
Shift/reduce conflict on token 'a':
shift/reduce conflict on token 'a':
10 reported_conflicts: . %empty
8 reported_conflicts: . 'a'
First example resolved_conflict . 'a' 'a'
@@ -1778,7 +1778,7 @@ State 4
`-> resolved_conflict reported_conflicts 'a'
`-> .
Shift/reduce conflict on token 'a':
shift/reduce conflict on token 'a':
10 reported_conflicts: . %empty
9 reported_conflicts: . 'a'
First example resolved_conflict . 'a' 'a'

68
tests/counterexample.at
View File

@@ -54,7 +54,7 @@ y: A | A B;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A . B C
Shift derivation
s
@@ -68,7 +68,7 @@ Shift/reduce conflict on token B:
input.y:4.4: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A . B C
Shift derivation s -> [ y -> [ A . B ] c -> [ C ] ]
Reduce derivation s -> [ a -> [ A . ] x -> [ B C ] ]
@@ -96,7 +96,7 @@ bc: B bc C | B C;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A . B C
Shift derivation
s
@@ -109,7 +109,7 @@ Shift/reduce conflict on token B:
`-> a bc
`-> A . `-> B C
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A A . B B C C
Shift derivation
s
@@ -128,12 +128,12 @@ Shift/reduce conflict on token B:
input.y:6.4: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A . B C
Shift derivation s -> [ ac -> [ A ac -> [ b -> [ . B ] ] C ] ]
Reduce derivation s -> [ a -> [ A . ] bc -> [ B C ] ]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A A . B B C C
Shift derivation s -> [ ac -> [ A ac -> [ A ac -> [ b -> [ . b -> [ B B ] ] ] C ] C ] ]
Reduce derivation s -> [ a -> [ A a -> [ A . ] ] bc -> [ B bc -> [ B C ] C ] ]
@@ -162,7 +162,7 @@ xby: B | X xby Y;
AT_BISON_CHECK_CEX(
[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A . B
Shift derivation
s
@@ -174,7 +174,7 @@ Shift/reduce conflict on token B:
`-> A x `-> B y
`-> . `-> %empty
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
First example A X . B Y $end
Shift derivation
$accept
@@ -194,12 +194,12 @@ Shift/reduce conflict on token B:
input.y:5.4-9: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example A . B
Shift derivation s -> [ A xby -> [ . B ] ]
Reduce derivation s -> [ ax -> [ A x -> [ . ] ] by -> [ B y -> [ ] ] ]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
First example A X . B Y $end
Shift derivation $accept -> [ s -> [ A xby -> [ X xby -> [ . B ] Y ] ] $end ]
Second example A X . B y $end
@@ -229,7 +229,7 @@ bc: B C;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token C:
input.y: warning: shift/reduce conflict on token C [-Wcounterexamples]
First example B . C $end
Shift derivation
$accept
@@ -248,7 +248,7 @@ Shift/reduce conflict on token C:
input.y:6.4: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token C:
input.y: warning: shift/reduce conflict on token C [-Wcounterexamples]
First example B . C $end
Shift derivation $accept -> [ g -> [ x -> [ bc -> [ B . C ] ] ] $end ]
Second example B . C D $end
@@ -276,7 +276,7 @@ y: A A B;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
First example A . A B $end
Shift derivation
$accept
@@ -295,7 +295,7 @@ Shift/reduce conflict on token A:
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
First example A . A B $end
Shift derivation $accept -> [ s -> [ t -> [ y -> [ A . A B ] ] ] $end ]
Second example A . A $end
@@ -327,7 +327,7 @@ y: Y;
AT_BISON_CHECK_CEX(
[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
Example b . A X X Y
Shift derivation
a
@@ -340,7 +340,7 @@ Shift/reduce conflict on token A:
`-> b . `-> A x xy
`-> X `-> X Y
Shift/reduce conflict on token X:
input.y: warning: shift/reduce conflict on token X [-Wcounterexamples]
First example A X . X
Shift derivation
a
@@ -357,12 +357,12 @@ input.y:4.4: warning: rule useless in parser due to conflicts [-Wother]
input.y:8.4: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
Example b . A X X Y
Shift derivation a -> [ s -> [ b . xx -> [ A X X ] y -> [ Y ] ] ]
Reduce derivation a -> [ r -> [ b . ] t -> [ A x -> [ X ] xy -> [ X Y ] ] ]
Shift/reduce conflict on token X:
input.y: warning: shift/reduce conflict on token X [-Wcounterexamples]
First example A X . X
Shift derivation a -> [ t -> [ A xx -> [ X . X ] ] ]
Second example X . X xy
@@ -472,7 +472,7 @@ i: X | i J K;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token J:
input.y: warning: shift/reduce conflict on token J [-Wcounterexamples]
time limit exceeded: XXX
First example H i . J K $end
Shift derivation
@@ -490,7 +490,7 @@ time limit exceeded: XXX
input.y:4.4-6: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token J:
input.y: warning: shift/reduce conflict on token J [-Wcounterexamples]
time limit exceeded: XXX
First example H i . J K $end
Shift derivation $accept -> [ a -> [ H i -> [ i . J K ] ] $end ]
@@ -522,7 +522,7 @@ b: A B C | A B D;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example N A . B C
Shift derivation
s
@@ -535,7 +535,7 @@ Shift/reduce conflict on token B:
`-> N a B
`-> A .
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example N N A . B D C
Shift derivation
s
@@ -553,12 +553,12 @@ Shift/reduce conflict on token B:
input.y:5.4: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example N A . B C
Shift derivation s -> [ n -> [ N b -> [ A . B C ] ] ]
Reduce derivation s -> [ n -> [ N a -> [ A . ] B ] C ]
Shift/reduce conflict on token B:
input.y: warning: shift/reduce conflict on token B [-Wcounterexamples]
Example N N A . B D C
Shift derivation s -> [ n -> [ N n -> [ N b -> [ A . B D ] ] C ] ]
Reduce derivation s -> [ n -> [ N n -> [ N a -> [ A . ] B ] D ] C ]
@@ -703,7 +703,7 @@ time limit exceeded: XXX
`-> c A
`-> .
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
time limit exceeded: XXX
First example b c . A
Shift derivation
@@ -742,7 +742,7 @@ input.y: warning: reduce/reduce conflict on token A [-Wcounterexamples]
`-> c A
`-> .
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
First example b c . A
Shift derivation
a
@@ -803,7 +803,7 @@ time limit exceeded: XXX
Second example c . A $end
Second derivation $accept -> [ a -> [ c d -> [ c -> [ . ] A ] ] $end ]
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
time limit exceeded: XXX
First example b c . A
Shift derivation a -> [ b d -> [ c . A ] ]
@@ -816,7 +816,7 @@ input.y: warning: reduce/reduce conflict on token A [-Wcounterexamples]
Second example b c . A $end
Second derivation $accept -> [ a -> [ b d -> [ a -> [ c d -> [ c -> [ . ] A ] ] ] ] $end ]
Shift/reduce conflict on token A:
input.y: warning: shift/reduce conflict on token A [-Wcounterexamples]
First example b c . A
Shift derivation a -> [ b d -> [ c . A ] ]
Second example b c . A $end
@@ -857,7 +857,7 @@ i: %empty | i J;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token J:
input.y: warning: shift/reduce conflict on token J [-Wcounterexamples]
Example H i J . J J
Shift derivation
s
@@ -872,7 +872,7 @@ Shift/reduce conflict on token J:
input.y:5.13-15: warning: rule useless in parser due to conflicts [-Wother]
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token J:
input.y: warning: shift/reduce conflict on token J [-Wcounterexamples]
Example H i J . J J
Shift derivation s -> [ a -> [ H i J . J ] J ]
Reduce derivation s -> [ a -> [ H i -> [ i J . ] J J ] ]
@@ -903,7 +903,7 @@ d: D;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token D:
input.y: warning: shift/reduce conflict on token D [-Wcounterexamples]
Example A a . D
Shift derivation
s
@@ -918,7 +918,7 @@ Shift/reduce conflict on token D:
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token D:
input.y: warning: shift/reduce conflict on token D [-Wcounterexamples]
Example A a . D
Shift derivation s -> [ A a d -> [ . D ] ]
Reduce derivation s -> [ A a a -> [ b -> [ c -> [ . ] ] ] d -> [ D ] ]
@@ -947,7 +947,7 @@ d: D;
AT_BISON_CHECK_CEX(
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token D:
input.y: warning: shift/reduce conflict on token D [-Wcounterexamples]
First example A a . D $end
Shift derivation
$accept
@@ -965,7 +965,7 @@ Shift/reduce conflict on token D:
]],
[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token D:
input.y: warning: shift/reduce conflict on token D [-Wcounterexamples]
First example A a . D $end
Shift derivation $accept -> [ s -> [ A a d -> [ . D ] ] $end ]
Second example A a . D E $end

8
tests/diagnostics.at
View File

@@ -535,7 +535,7 @@ exp
| exp "+" exp
| "num"
]],
[1],
[1],
[[input.y: <error>error:</error> shift/reduce conflicts: 4 found, 0 expected
input.y: <warning>warning:</warning> shift/reduce conflict on token "+" [<warning>-Wcounterexamples</warning>]
Example <cex-0><cex-leaf>exp</cex-leaf> <cex-leaf>"+"</cex-leaf><cex-1> <cex-leaf>exp</cex-leaf> <cex-dot>•</cex-dot> <cex-leaf>"+"</cex-leaf> <cex-leaf>exp</cex-leaf></cex-1></cex-0>
@@ -547,7 +547,7 @@ Shift/reduce conflict on token "+":
Reduce derivation
<cex-0><cex-step>exp</cex-step></cex-0>
<cex-0><cex-step>↳ <cex-1><cex-step>exp</cex-step></cex-1><cex-leaf> "+"</cex-leaf><cex-leaf> exp</cex-leaf></cex-step></cex-0>
<cex-1><cex-step> ↳ <cex-leaf>exp</cex-leaf><cex-leaf> "+"</cex-leaf><cex-leaf> exp</cex-leaf><cex-dot> •</cex-dot></cex-step></cex-1>
<cex-1><cex-step> ↳ <cex-leaf>exp</cex-leaf><cex-leaf> "+"</cex-leaf><cex-leaf> exp</cex-leaf><cex-dot> •</cex-dot></cex-step></cex-1>
input.y: <warning>warning:</warning> shift/reduce conflict on token "else" [<warning>-Wcounterexamples</warning>]
Example <cex-0><cex-leaf>"if"</cex-leaf> <cex-leaf>exp</cex-leaf> <cex-leaf>"then"</cex-leaf><cex-1> <cex-leaf>"if"</cex-leaf> <cex-leaf>exp</cex-leaf> <cex-leaf>"then"</cex-leaf> <cex-leaf>exp</cex-leaf> <cex-dot>•</cex-dot> <cex-leaf>"else"</cex-leaf> <cex-leaf>exp</cex-leaf></cex-1></cex-0>
@@ -559,7 +559,7 @@ Shift/reduce conflict on token "else":
Reduce derivation
<cex-0><cex-step>exp</cex-step></cex-0>
<cex-0><cex-step>↳ <cex-leaf>"if"</cex-leaf><cex-leaf> exp</cex-leaf><cex-leaf> "then"</cex-leaf><cex-1><cex-step> exp</cex-step></cex-1><cex-leaf> "else"</cex-leaf><cex-leaf> exp</cex-leaf></cex-step></cex-0>
<cex-1><cex-step> ↳ <cex-leaf>"if"</cex-leaf><cex-leaf> exp</cex-leaf><cex-leaf> "then"</cex-leaf><cex-leaf> exp</cex-leaf><cex-dot> •</cex-dot></cex-step></cex-1>
<cex-1><cex-step> ↳ <cex-leaf>"if"</cex-leaf><cex-leaf> exp</cex-leaf><cex-leaf> "then"</cex-leaf><cex-leaf> exp</cex-leaf><cex-dot> •</cex-dot></cex-step></cex-1>
input.y: <warning>warning:</warning> shift/reduce conflict on token "+" [<warning>-Wcounterexamples</warning>]
Example <cex-0><cex-leaf>"if"</cex-leaf> <cex-leaf>exp</cex-leaf> <cex-leaf>"then"</cex-leaf><cex-1> <cex-leaf>exp</cex-leaf> <cex-dot>•</cex-dot> <cex-leaf>"+"</cex-leaf> <cex-leaf>exp</cex-leaf></cex-1></cex-0>
@@ -571,7 +571,7 @@ Shift/reduce conflict on token "+":
Reduce derivation
<cex-0><cex-step>exp</cex-step></cex-0>
<cex-0><cex-step>↳ <cex-1><cex-step>exp</cex-step></cex-1><cex-leaf> "+"</cex-leaf><cex-leaf> exp</cex-leaf></cex-step></cex-0>
<cex-1><cex-step> ↳ <cex-leaf>"if"</cex-leaf><cex-leaf> exp</cex-leaf><cex-leaf> "then"</cex-leaf><cex-leaf> exp</cex-leaf><cex-dot> •</cex-dot></cex-step></cex-1>
<cex-1><cex-step> ↳ <cex-leaf>"if"</cex-leaf><cex-leaf> exp</cex-leaf><cex-leaf> "then"</cex-leaf><cex-leaf> exp</cex-leaf><cex-dot> •</cex-dot></cex-step></cex-1>
input.y: <warning>warning:</warning> shift/reduce conflict on token "+" [<warning>-Wcounterexamples</warning>]
Example <cex-0><cex-leaf>"if"</cex-leaf> <cex-leaf>exp</cex-leaf> <cex-leaf>"then"</cex-leaf> <cex-leaf>exp</cex-leaf> <cex-leaf>"else"</cex-leaf><cex-1> <cex-leaf>exp</cex-leaf> <cex-dot>•</cex-dot> <cex-leaf>"+"</cex-leaf> <cex-leaf>exp</cex-leaf></cex-1></cex-0>

20
tests/report.at
View File

@@ -1537,7 +1537,7 @@ exp
AT_CHECK([LC_ALL="$locale" bison -fno-caret -o input.cc -rall -Wcex --graph=input.gv --xml input.y], [], [],
[[input.y: warning: 3 shift/reduce conflicts [-Wconflicts-sr]
input.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
Shift/reduce conflict on token "⊕":
input.y: warning: shift/reduce conflict on token "⊕" [-Wcounterexamples]
Example exp "+" exp • "⊕" exp
Shift derivation
exp
@@ -1557,7 +1557,7 @@ input.y: warning: reduce/reduce conflict on tokens $end, "+", "⊕" [-Wcounterex
exp
↳ exp "+" exp •
Shift/reduce conflict on token "⊕":
input.y: warning: shift/reduce conflict on token "⊕" [-Wcounterexamples]
Example exp "+" exp • "⊕" exp
Shift derivation
exp
@@ -1568,7 +1568,7 @@ Shift/reduce conflict on token "⊕":
↳ exp "⊕" exp
↳ exp "+" exp •
Shift/reduce conflict on token "⊕":
input.y: warning: shift/reduce conflict on token "⊕" [-Wcounterexamples]
Example exp "⊕" exp • "⊕" exp
Shift derivation
exp
@@ -1579,7 +1579,7 @@ Shift/reduce conflict on token "⊕":
↳ exp "⊕" exp
↳ exp "⊕" exp •
Shift/reduce conflict on token "+":
input.y: warning: shift/reduce conflict on token "+" [-Wcounterexamples]
Example exp "⊕" exp • "+" exp
Shift derivation
exp
@@ -1590,7 +1590,7 @@ Shift/reduce conflict on token "+":
↳ exp "+" exp
↳ exp "⊕" exp •
Shift/reduce conflict on token "+":
input.y: warning: shift/reduce conflict on token "+" [-Wcounterexamples]
Example exp "⊕" exp • "+" exp
Shift derivation
exp
@@ -1745,7 +1745,7 @@ State 7
Conflict between rule 2 and token "+" resolved as reduce (%left "+").
Shift/reduce conflict on token "⊕":
shift/reduce conflict on token "⊕":
2 exp: exp "+" exp •
1 exp: exp • "⊕" exp
Example exp "+" exp • "⊕" exp
@@ -1769,7 +1769,7 @@ State 7
exp
↳ exp "+" exp •
Shift/reduce conflict on token "⊕":
shift/reduce conflict on token "⊕":
3 exp: exp "+" exp •
1 exp: exp • "⊕" exp
Example exp "+" exp • "⊕" exp
@@ -1798,7 +1798,7 @@ State 8
"⊕" [reduce using rule 1 (exp)]
$default reduce using rule 1 (exp)
Shift/reduce conflict on token "⊕":
shift/reduce conflict on token "⊕":
1 exp: exp "⊕" exp •
1 exp: exp • "⊕" exp
Example exp "⊕" exp • "⊕" exp
@@ -1811,7 +1811,7 @@ State 8
↳ exp "⊕" exp
↳ exp "⊕" exp •
Shift/reduce conflict on token "+":
shift/reduce conflict on token "+":
1 exp: exp "⊕" exp •
2 exp: exp • "+" exp
Example exp "⊕" exp • "+" exp
@@ -1824,7 +1824,7 @@ State 8
↳ exp "+" exp
↳ exp "⊕" exp •
Shift/reduce conflict on token "+":
shift/reduce conflict on token "+":
1 exp: exp "⊕" exp •
3 exp: exp • "+" exp
Example exp "⊕" exp • "+" exp