Must force a type when dealing with compound types

This commit is contained in:
2022-08-22 14:27:41 +01:00
parent 300f8e382b
commit 5b82ed8e45
4 changed files with 26 additions and 13 deletions

View File

@@ -24,6 +24,7 @@ TODO: functions are first-class citizens
TODO: functions last argument can be a rest parameter
TODO: && and || operators
TODO: += -= *= /= %= operators
TODO: A way to check the type of a variable (typeOf keyword)
TODO: a = b = c = 1; ?
TODO: are compounds shallow or deep copies?

View File

@@ -118,6 +118,16 @@ var t: type = int;
var u: t = 42;
```
To force a type instead of an array, use the `type` keyword:
```
var a = [type type]; //array of types
var b = type [type]; //type of array of types
var c = [type]; //error!
var d = b; //types can be re-assigned to other variables
```
## Const
The "const" keyword can be appended to the type of a variable to fix the value in place - constants, as they're known, can't be changed once they are given a value at declaration.

View File

@@ -78,7 +78,6 @@ static void synchronize(Parser* parser) {
case TOKEN_IMPORT:
case TOKEN_PRINT:
case TOKEN_RETURN:
case TOKEN_TYPE:
case TOKEN_VAR:
case TOKEN_WHILE:
parser->panic = false;
@@ -119,8 +118,17 @@ ParseRule parseRules[];
//forward declarations
static void declaration(Parser* parser, Node** nodeHandle);
static void parsePrecedence(Parser* parser, Node** nodeHandle, PrecedenceRule rule);
static Literal readTypeToLiteral(Parser* parser);
//the expression rules
static Opcode forceType(Parser* parser, Node** nodeHandle) {
Literal literal = readTypeToLiteral(parser);
emitNodeLiteral(nodeHandle, literal);
return OP_EOF;
}
static Opcode compound(Parser* parser, Node** nodeHandle) {
//read either an array or a dictionary into a literal node
@@ -615,7 +623,7 @@ ParseRule parseRules[] = { //must match the token types
{NULL, NULL, PREC_NONE},// TOKEN_OF,
{NULL, NULL, PREC_NONE},// TOKEN_PRINT,
{NULL, NULL, PREC_NONE},// TOKEN_RETURN,
{NULL, NULL, PREC_NONE},// TOKEN_USING,
{forceType, NULL, PREC_PRIMARY},// TOKEN_TYPE,
{NULL, NULL, PREC_NONE},// TOKEN_VAR,
{NULL, NULL, PREC_NONE},// TOKEN_WHILE,
@@ -1231,15 +1239,8 @@ static void varDecl(Parser* parser, Node** nodeHandle) {
//variable definition is an expression
Node* expressionNode = NULL;
if (match(parser, TOKEN_ASSIGN)) {
//BUGFIX: if reading into a "type" variable, expect a type value
if (AS_TYPE(typeLiteral).typeOf == LITERAL_TYPE) { //This may cause issues when reading function returns
Literal val = readTypeToLiteral(parser);
emitNodeLiteral(&expressionNode, val);
} else {
expression(parser, &expressionNode);
}
}
else {
//values are null by default
emitNodeLiteral(&expressionNode, TO_NULL_LITERAL);

View File

@@ -7,14 +7,15 @@ assert u == 42, "first-class types are screwing with values";
//differentiate by the "type" value
var v: type = [int]; //TODO: still can't check for this
var v: type = type [int];
var w = [int];
var x = v;
assert w == [int], "defining an array of types failed";
assert x == type [int], "re-assigning a type value failed";
//complex type
var complex: type = [string, [int]];
var complex: type = type [string, [int]];
var dict: complex = [
"first array": [1, 2, 3],
"second array": [4, 5, 6],