/*
 * test_formatter_precedence_grammar.lime -- regression fixture for
 * Lime-Letter-22 (PostgreSQL migration team).
 *
 * v0.3.0 through v0.3.5 silently dropped %left / %right / %nonassoc
 * precedence directives during `lime -F`, causing every binary-op
 * rule to become shift/reduce-ambiguous in the formatted output.
 * On PG's gram.lime the canonicalize-the-source pass exploded from
 * 0 conflicts to 1682.
 *
 * This fixture has 4 binary operators with three precedence levels
 * + one unary precedence override.  Source compiles with 0 parsing
 * conflicts.  The driver test asserts the formatted output also
 * compiles with 0 conflicts -- if the precedence directives are
 * dropped, the binary-op rules introduce 8+ new conflicts.
 */

%name FmtPrec
%token_type {int}
%type expr {int}
%extra_argument {int *out}

%token PLUS MINUS TIMES DIVIDE LPAREN RPAREN INTEGER UMINUS.

%left PLUS MINUS.
%left TIMES DIVIDE.
%right UMINUS.

%start_symbol program

program(P) ::= expr(E).             { P = E; *out = E; }

expr(R) ::= expr(L) PLUS expr(M).   { R = L + M; }
expr(R) ::= expr(L) MINUS expr(M).  { R = L - M; }
expr(R) ::= expr(L) TIMES expr(M).  { R = L * M; }
expr(R) ::= expr(L) DIVIDE expr(M). { R = (M != 0) ? L / M : 0; }
expr(R) ::= MINUS expr(M). [UMINUS] { R = -M; }
expr(R) ::= LPAREN expr(M) RPAREN.  { R = M; }
expr(R) ::= INTEGER(N).             { R = N; }