$void
OpenScope -> ${ scope_push(c); }$
+ ClosePara -> ${ var_block_close(c, CloseParallel); }$
Each variable records a scope depth and is in one of four states:
}
###### top level grammar
- DeclareStruct -> struct IDENTIFIER FieldBlock ${ {
+ DeclareStruct -> struct IDENTIFIER FieldBlock Newlines ${ {
struct type *t =
add_type(c, $2.txt, &structure_prototype);
int cnt = 0;
f = f->prev;
}
} }$
- | DeclareStruct NEWLINE
- $void
- Newlines -> NEWLINE
- | Newlines NEWLINE
- Open -> {
- | Newlines {
- Close -> }
- | Newlines }
$*fieldlist
- FieldBlock -> Open FieldList } ${ $0 = $<2; }$
- | Open SimpleFieldList } ${ $0 = $<2; }$
- | : FieldList ${ $0 = $<2; }$
-
- FieldList -> FieldLines ${ $0 = $<1; }$
- | Newlines FieldLines ${ $0 = $<2; }$
- FieldLines -> SimpleFieldListLine ${ $0 = $<1; }$
- | FieldLines SimpleFieldListLine ${
- $2->prev = $<1;
- $0 = $<2;
+ FieldBlock -> { IN OptNL FieldLines OUT OptNL } ${ $0 = $<FL; }$
+ | { SimpleFieldList } ${ $0 = $<SFL; }$
+ | IN OptNL FieldLines OUT ${ $0 = $<FL; }$
+ | SimpleFieldList EOL ${ $0 = $<SFL; }$
+
+ FieldLines -> SimpleFieldList Newlines ${ $0 = $<SFL; }$
+ | FieldLines SimpleFieldList Newlines ${
+ $SFL->prev = $<FL;
+ $0 = $<SFL;
}$
- SimpleFieldListLine -> SimpleFieldList NEWLINE ${ $0 = $<1; }$
- | SimpleFieldListLine NEWLINE ${ $0 = $<1; }$
- | ERROR NEWLINE ${ tok_err(c, "Syntax error in struct field", &$1); }$
-
- SimpleFieldList -> Field ${ $0 = $<1; }$
+ SimpleFieldList -> Field ${ $0 = $<F; }$
| SimpleFieldList ; Field ${
- $3->prev = $<1;
- $0 = $<3;
+ $F->prev = $<SFL;
+ $0 = $<F;
}$
| SimpleFieldList ; ${
- $0 = $<1;
+ $0 = $<SFL;
}$
+ | ERROR ${ tok_err(c, "Syntax error in struct field", &$1); }$
Field -> IDENTIFIER : Type = Expression ${ {
int ok;
{
int i;
- fprintf(f, "struct %.*s:\n", t->name.len, t->name.txt);
+ fprintf(f, "struct %.*s\n", t->name.len, t->name.txt);
for (i = 0; i < t->structure.nfields; i++) {
struct field *fl = t->structure.fields + i;
$LEFT + - Eop
$LEFT * / % ++ Top
$LEFT Uop
+ $TERM ( )
###### expression grammar
| Expression Eop Expression ${ {
###### Binode types
Block,
+###### expr precedence
+ $TERM pass
+
###### Grammar
$*binode
- Block -> Open Statementlist Close ${ $0 = $<2; }$
- | Open SimpleStatements } ${ $0 = reorder_bilist($<2); }$
- | : SimpleStatements ${ $0 = reorder_bilist($<2); }$
- | : Statementlist ${ $0 = $<2; }$
-
- Statementlist -> ComplexStatements ${ $0 = reorder_bilist($<1); }$
- | Newlines ComplexStatements ${ $0 = reorder_bilist($<2); }$
+ Block -> { IN OptNL Statementlist OUT OptNL } ${ $0 = $<Sl; }$
+ | { SimpleStatements } ${ $0 = reorder_bilist($<SS); }$
+ | SimpleStatements ; ${ $0 = reorder_bilist($<SS); }$
+ | SimpleStatements EOL ${ $0 = reorder_bilist($<SS); }$
+ | IN OptNL Statementlist OUT ${ $0 = $<Sl; }$
+
+ OpenBlock -> OpenScope { IN OptNL Statementlist OUT OptNL } ${ $0 = $<Sl; }$
+ | OpenScope { SimpleStatements } ${ $0 = reorder_bilist($<SS); }$
+ | OpenScope SimpleStatements ; ${ $0 = reorder_bilist($<SS); }$
+ | OpenScope SimpleStatements EOL ${ $0 = reorder_bilist($<SS); }$
+ | IN OpenScope OptNL Statementlist OUT ${ $0 = $<Sl; }$
+
+ UseBlock -> { OpenScope IN OptNL Statementlist OUT OptNL } ${ $0 = $<Sl; }$
+ | { OpenScope SimpleStatements } ${ $0 = reorder_bilist($<SS); }$
+ | IN OpenScope OptNL Statementlist OUT ${ $0 = $<Sl; }$
+
+ ColonBlock -> { IN OptNL Statementlist OUT OptNL } ${ $0 = $<Sl; }$
+ | { SimpleStatements } ${ $0 = reorder_bilist($<SS); }$
+ | : SimpleStatements ; ${ $0 = reorder_bilist($<SS); }$
+ | : SimpleStatements EOL ${ $0 = reorder_bilist($<SS); }$
+ | : IN OptNL Statementlist OUT ${ $0 = $<Sl; }$
+
+ Statementlist -> ComplexStatements ${ $0 = reorder_bilist($<CS); }$
ComplexStatements -> ComplexStatements ComplexStatement ${
if ($2 == NULL) {
}$
$*exec
- ComplexStatement -> SimpleStatementLine ${
- $0 = reorder_bilist($<1);
+ ComplexStatement -> SimpleStatements Newlines ${
+ $0 = reorder_bilist($<SS);
+ }$
+ | SimpleStatements ; Newlines ${
+ $0 = reorder_bilist($<SS);
}$
- | ComplexStatement NEWLINE ${ $0 = $<1; }$
## ComplexStatement Grammar
$*binode
$0->right = $<1;
}$
- SimpleStatementLine -> SimpleStatements NEWLINE ${ $0 = $<1; }$
- | SimpleStatements ; NEWLINE ${ $0 = $<1; }$
- | SimpleStatementLine NEWLINE ${ $0 = $<1; }$
-
SimpleStatement -> pass ${ $0 = NULL; }$
| ERROR ${ tok_err(c, "Syntax error in statement", &$1); }$
## SimpleStatement Grammar
###### Binode types
Print,
+##### expr precedence
+ $TERM print ,
+
###### SimpleStatement Grammar
| print ExpressionList ${
###### Binode types
Use,
+###### expr precedence
+ $TERM use
+
###### SimpleStatement Grammar
| use Expression ${
$0 = new_pos(binode, $1);
###### ComplexStatement Grammar
| CondStatement ${ $0 = $<1; }$
+###### expr precedence
+ $TERM for then while do
+ $TERM else
+ $TERM switch case
+
###### Grammar
$*cond_statement
- // both ForThen and Whilepart open scopes, and CondSuffix only
+ // A CondStatement must end with EOL, as does CondSuffix and
+ // IfSuffix.
+ // ForPart, ThenPart, SwitchPart, CasePart are non-empty and
+ // may or may not end with EOL
+ // WhilePart and IfPart include an appropriate Suffix
+
+
+ // Both ForPart and Whilepart open scopes, and CondSuffix only
// closes one - so in the first branch here we have another to close.
- CondStatement -> ForPart ThenPart WhilePart CondSuffix ${
- $0 = $<4;
- $0->forpart = $<1;
- $0->thenpart = $<2;
- $0->condpart = $3.condpart; $3.condpart = NULL;
- $0->dopart = $3.dopart; $3.dopart = NULL;
+ CondStatement -> ForPart OptNL ThenPart OptNL WhilePart CondSuffix ${
+ $0 = $<CS;
+ $0->forpart = $<FP;
+ $0->thenpart = $<TP;
+ $0->condpart = $WP.condpart; $WP.condpart = NULL;
+ $0->dopart = $WP.dopart; $WP.dopart = NULL;
var_block_close(c, CloseSequential);
}$
- | ForPart WhilePart CondSuffix ${
- $0 = $<3;
- $0->forpart = $<1;
- $0->thenpart = NULL;
- $0->condpart = $2.condpart; $2.condpart = NULL;
- $0->dopart = $2.dopart; $2.dopart = NULL;
+ | ForPart OptNL WhilePart CondSuffix ${
+ $0 = $<CS;
+ $0->forpart = $<FP;
+ $0->condpart = $WP.condpart; $WP.condpart = NULL;
+ $0->dopart = $WP.dopart; $WP.dopart = NULL;
var_block_close(c, CloseSequential);
}$
| WhilePart CondSuffix ${
- $0 = $<2;
- $0->condpart = $1.condpart; $1.condpart = NULL;
- $0->dopart = $1.dopart; $1.dopart = NULL;
+ $0 = $<CS;
+ $0->condpart = $WP.condpart; $WP.condpart = NULL;
+ $0->dopart = $WP.dopart; $WP.dopart = NULL;
+ }$
+ | SwitchPart OptNL CasePart CondSuffix ${
+ $0 = $<CS;
+ $0->condpart = $<SP;
+ $CP->next = $0->casepart;
+ $0->casepart = $<CP;
}$
- | SwitchPart CasePart CondSuffix ${
- $0 = $<3;
- $0->condpart = $<1;
- $2->next = $0->casepart;
- $0->casepart = $<2;
+ | SwitchPart : IN OptNL CasePart CondSuffix OUT Newlines ${
+ $0 = $<CS;
+ $0->condpart = $<SP;
+ $CP->next = $0->casepart;
+ $0->casepart = $<CP;
}$
| IfPart IfSuffix ${
- $0 = $<2;
- $0->condpart = $1.condpart; $1.condpart = NULL;
- $0->thenpart = $1.thenpart; $1.thenpart = NULL;
+ $0 = $<IS;
+ $0->condpart = $IP.condpart; $IP.condpart = NULL;
+ $0->thenpart = $IP.thenpart; $IP.thenpart = NULL;
// This is where we close an "if" statement
var_block_close(c, CloseSequential);
}$
// "for" or "while" statement
var_block_close(c, CloseSequential);
}$
+ | Newlines CasePart CondSuffix ${
+ $0 = $<CS;
+ $CP->next = $0->casepart;
+ $0->casepart = $<CP;
+ }$
| CasePart CondSuffix ${
- $0 = $<2;
- $1->next = $0->casepart;
- $0->casepart = $<1;
+ $0 = $<CS;
+ $CP->next = $0->casepart;
+ $0->casepart = $<CP;
}$
- $*casepart
- CasePart -> case Expression OpenScope Block ${
- $0 = calloc(1,sizeof(struct casepart));
- $0->value = $<2;
- $0->action = $<4;
- var_block_close(c, CloseParallel);
- }$
- | CasePart NEWLINE ${ $0 = $<1; }$
+ IfSuffix -> Newlines ${ $0 = new(cond_statement); }$
+ | Newlines ElsePart ${ $0 = $<EP; }$
+ | ElsePart ${$0 = $<EP; }$
- $*cond_statement
- IfSuffix -> ${ $0 = new(cond_statement); }$
- | IfSuffix NEWLINE ${ $0 = $<1; }$
- | else OpenScope Block ${
+ ElsePart -> else OpenBlock Newlines ${
$0 = new(cond_statement);
- $0->elsepart = $<3;
- var_block_close(c, CloseElse);
- }$
- | else OpenScope SimpleStatements NEWLINE ${
- $0 = new(cond_statement);
- $0->elsepart = reorder_bilist($<3);
+ $0->elsepart = $<OB;
var_block_close(c, CloseElse);
}$
| else OpenScope CondStatement ${
$0 = new(cond_statement);
- $0->elsepart = $<3;
+ $0->elsepart = $<CS;
var_block_close(c, CloseElse);
}$
+ $*casepart
+ CasePart -> case Expression OpenScope ColonBlock ${
+ $0 = calloc(1,sizeof(struct casepart));
+ $0->value = $<Ex;
+ $0->action = $<Bl;
+ var_block_close(c, CloseParallel);
+ }$
+
$*exec
// These scopes are closed in CondSuffix
- ForPart -> for OpenScope SimpleStatements ; ${
- $0 = reorder_bilist($<3);
+ ForPart -> for OpenBlock ${
+ $0 = $<Bl;
}$
- | for OpenScope SimpleStatements NEWLINE ${
- $0 = reorder_bilist($<3);
- }$
- | for OpenScope Block ${
- $0 = $<3;
- }$
- | ForPart NEWLINE ${ $0 = $<1; }$
- ThenPart -> then OpenScope SimpleStatements ; ${
- $0 = reorder_bilist($<3);
- var_block_close(c, CloseSequential);
- }$
- | then OpenScope SimpleStatements NEWLINE ${
- $0 = reorder_bilist($<3);
+ ThenPart -> then OpenBlock ${
+ $0 = $<OB;
var_block_close(c, CloseSequential);
}$
- | then OpenScope Block ${
- $0 = $<3;
- var_block_close(c, CloseSequential);
- }$
- | ThenPart NEWLINE ${ $0 = $<1; }$
-
- // This scope is closed in CondSuffix
- WhileHead -> while OpenScope Block ${ $0 = $<3; }$
- | WhileHead NEWLINE ${ $0 = $<1; }$
$cond_statement
// This scope is closed in CondSuffix
- WhilePart -> while OpenScope Expression Block ${
- $0.type = Xcond_statement;
- $0.condpart = $<3;
- $0.dopart = $<4;
+ WhilePart -> while UseBlock OptNL do Block ${
+ $0.condpart = $<UB;
+ $0.dopart = $<Bl;
}$
- | WhileHead do Block ${
- $0.type = Xcond_statement;
- $0.condpart = $<1;
- $0.dopart = $<3;
+ | while OpenScope Expression ColonBlock ${
+ $0.condpart = $<Exp;
+ $0.dopart = $<Bl;
}$
- | WhilePart NEWLINE ${ $0 = $<1; }$
- IfPart -> if OpenScope Expression OpenScope Block ${
- $0.type = Xcond_statement;
- $0.condpart = $<3;
- $0.thenpart = $<5;
- var_block_close(c, CloseParallel);
- }$
- | if OpenScope Expression OpenScope then Block ${
- $0.type = Xcond_statement;
- $0.condpart = $<3;
- $0.thenpart = $<6;
- var_block_close(c, CloseParallel);
- }$
- | if OpenScope Expression OpenScope then SimpleStatements ; ${
- $0.type = Xcond_statement;
- $0.condpart = $<3;
- $0.thenpart = reorder_bilist($<6);
- var_block_close(c, CloseParallel);
+ IfPart -> if UseBlock OptNL then OpenBlock ClosePara ${
+ $0.condpart = $<UB;
+ $0.thenpart = $<Bl;
}$
- | if OpenScope Expression OpenScope then SimpleStatements NEWLINE ${
- $0.type = Xcond_statement;
- $0.condpart = $<3;
- $0.thenpart = reorder_bilist($<6);
- var_block_close(c, CloseParallel);
+ | if OpenScope Expression OpenScope ColonBlock ClosePara ${
+ $0.condpart = $<Ex;
+ $0.thenpart = $<Bl;
}$
- | if OpenScope Block then OpenScope Block ${
- $0.type = Xcond_statement;
- $0.condpart = $<3;
- $0.thenpart = $<6;
- var_block_close(c, CloseParallel);
+ | if OpenScope Expression OpenScope OptNL then Block ClosePara ${
+ $0.condpart = $<Ex;
+ $0.thenpart = $<Bl;
}$
- | IfPart NEWLINE ${ $0 = $<1; }$
$*exec
// This scope is closed in CondSuffix
SwitchPart -> switch OpenScope Expression ${
- $0 = $<3;
+ $0 = $<Ex;
}$
- | switch OpenScope Block ${
- $0 = $<3;
+ | switch UseBlock ${
+ $0 = $<Bl;
}$
- | SwitchPart NEWLINE ${ $0 = $<1; }$
###### print exec cases
struct casepart *cp;
if (cs->forpart) {
do_indent(indent, "for");
- if (bracket) printf(" {\n"); else printf(":\n");
+ if (bracket) printf(" {\n"); else printf("\n");
print_exec(cs->forpart, indent+1, bracket);
if (cs->thenpart) {
if (bracket)
do_indent(indent, "} then {\n");
else
- do_indent(indent, "then:\n");
+ do_indent(indent, "then\n");
print_exec(cs->thenpart, indent+1, bracket);
}
if (bracket) do_indent(indent, "}\n");
if (bracket)
do_indent(indent, "while {\n");
else
- do_indent(indent, "while:\n");
+ do_indent(indent, "while\n");
print_exec(cs->condpart, indent+1, bracket);
if (bracket)
do_indent(indent, "} do {\n");
else
- do_indent(indent, "do:\n");
+ do_indent(indent, "do\n");
print_exec(cs->dopart, indent+1, bracket);
if (bracket)
do_indent(indent, "}\n");
if (bracket)
printf(" {\n");
else
- printf(":\n");
+ printf("\n");
print_exec(cs->elsepart, indent+1, bracket);
if (bracket)
do_indent(indent, "}\n");
###### Parser: grammar
$void
- Ocean -> DeclarationList
- | Newlines DeclarationList
+ Ocean -> OptNL DeclarationList
+
+ OptNL ->
+ | OptNL NEWLINE
+ Newlines -> NEWLINE
+ | Newlines NEWLINE
DeclarationList -> Declaration
| DeclarationList Declaration
- Declaration -> Declaration NEWLINE
- | DeclareConstant
- | DeclareProgram
- | DeclareStruct
- | ERROR NEWLINE ${
+ Declaration -> ERROR Newlines ${
tok_err(c,
"error: unhandled parse error", &$1);
}$
+ | DeclareConstant
+ | DeclareProgram
+ | DeclareStruct
## top level grammar
###### top level grammar
- DeclareConstant -> const Open ConstList Close
- | const Open SimpleConstList }
- | const : ConstList
- | const SimpleConstList NEWLINE
+ DeclareConstant -> const { IN OptNL ConstList OUT OptNL } Newlines
+ | const { SimpleConstList } Newlines
+ | const IN OptNL ConstList OUT Newlines
+ | const SimpleConstList Newlines
- ConstList -> ConstLines
- | Newlines ConstLines
- ConstLines -> ConstLines SimpleConstLine
+ ConstList -> ConstList SimpleConstLine
| SimpleConstLine
SimpleConstList -> SimpleConstList ; Const
| Const
| SimpleConstList ;
- SimpleConstLine -> SimpleConstList NEWLINE
- | SimpleConstLine NEWLINE
- | ERROR NEWLINE ${ tok_err(c, "Syntax error in constant", &$1); }$
+ SimpleConstLine -> SimpleConstList Newlines
+ | ERROR Newlines ${ tok_err(c, "Syntax error in constant", &$1); }$
$*type
CType -> Type ${ $0 = $<1; }$
if (target == -1) {
if (i)
- printf("const:\n");
+ printf("const\n");
target = i;
} else {
printf(" %.*s :: ", v->name->name.len, v->name->name.txt);
} }$
$*binode
- Program -> program OpenScope Varlist Block ${
+ Program -> program OpenScope Varlist ColonBlock Newlines ${
$0 = new(binode);
$0->op = Program;
- $0->left = reorder_bilist($<3);
- $0->right = $<4;
+ $0->left = reorder_bilist($<Vl);
+ $0->right = $<Bl;
var_block_close(c, CloseSequential);
if (c->scope_stack && !c->parse_error) abort();
}$
###### demo: hello
- const:
+ const
pi ::= 3.141_592_6
four ::= 2 + 2 ; five ::= 10/2
const pie ::= "I like Pie";
cake ::= "The cake is"
++ " a lie"
- struct fred:
+ struct fred
size:[four]number
name:string
alive:Boolean
*/
if A > B:
bigger := "yes"
- else:
+ else
bigger := "no"
print "Is", A, "bigger than", B,"? ", bigger
/* If a variable is not used after the 'if', no
if A > B * 2:
double:string = "yes"
print A, "is more than twice", B, "?", double
- else:
+ else
double := B*2
print "double", B, "is", double
while a != b:
if a < b:
b = b - a
- else:
+ else
a = a - b
print "GCD of", A, "and", B,"is", a
else if a <= 0:
print a, "is not positive, cannot calculate GCD"
- else:
+ else
print b, "is not positive, cannot calculate GCD"
- for:
+ for
togo := 10
f1 := 1; f2 := 1
print "Fibonacci:", f1,f2,
print ""
/* Binary search... */
- for:
+ for
lo:= 0; hi := 100
target := 77
- while:
+ while
mid := (lo + hi) / 2
if mid == target:
use Found
if mid < target:
lo = mid
- else:
+ else
hi = mid
if hi - lo < 1:
use GiveUp
use True
- do: pass
+ do pass
case Found:
print "Yay, I found", target
case GiveUp:
code / ocean / blobdiff