topchetoeu/j2s
1
0
Fork 0
Code Issues 6 Pull Requests Actions Packages Projects Releases 74 Wiki Activity

feat: add simple for-of loop (not intended for production usage)

Browse Source
This commit is contained in:
TopchetoEU 2024-03-27 23:08:21 +02:00
parent d8ea6557df
commit e0f3274a95
Signed by: topchetoeu
GPG Key ID: 6531B8583E5F6ED4
2 changed files with 114 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

73
src/java/me/topchetoeu/jscript/compilation/control/ForOfStatement.java Normal file
View File

@ -0,0 +1,73 @@
package me.topchetoeu.jscript.compilation.control;
import me.topchetoeu.jscript.common.Instruction;
import me.topchetoeu.jscript.common.Location;
import me.topchetoeu.jscript.common.Instruction.BreakpointType;
import me.topchetoeu.jscript.compilation.CompileResult;
import me.topchetoeu.jscript.compilation.Statement;
public class ForOfStatement extends Statement {
public final String varName;
public final boolean isDeclaration;
public final Statement iterable, body;
public final String label;
public final Location varLocation;
@Override
public void declare(CompileResult target) {
body.declare(target);
if (isDeclaration) target.scope.define(varName);
}
@Override
public void compile(CompileResult target, boolean pollute) {
var key = target.scope.getKey(varName);
if (key instanceof String) target.add(Instruction.makeVar((String)key));
iterable.compile(target, true, BreakpointType.STEP_OVER);
target.add(Instruction.dup());
target.add(Instruction.loadVar("Symbol"));
target.add(Instruction.pushValue("iterator"));
target.add(Instruction.loadMember()).setLocation(iterable.loc());
target.add(Instruction.loadMember()).setLocation(iterable.loc());
target.add(Instruction.call(0)).setLocation(iterable.loc());
int start = target.size();
target.add(Instruction.dup());
target.add(Instruction.dup());
target.add(Instruction.pushValue("next"));
target.add(Instruction.loadMember()).setLocation(iterable.loc());
target.add(Instruction.call(0)).setLocation(iterable.loc());
target.add(Instruction.dup());
target.add(Instruction.pushValue("done"));
target.add(Instruction.loadMember()).setLocation(iterable.loc());
int mid = target.temp();
target.add(Instruction.pushValue("value"));
target.add(Instruction.loadMember()).setLocation(varLocation);
target.add(Instruction.storeVar(key)).setLocationAndDebug(iterable.loc(), BreakpointType.STEP_OVER);
body.compile(target, false, BreakpointType.STEP_OVER);
int end = target.size();
WhileStatement.replaceBreaks(target, label, mid + 1, end, start, end + 1);
target.add(Instruction.jmp(start - end));
target.add(Instruction.discard());
target.add(Instruction.discard());
target.set(mid, Instruction.jmpIf(end - mid + 1));
if (pollute) target.add(Instruction.pushUndefined());
}
public ForOfStatement(Location loc, Location varLocation, String label, boolean isDecl, String varName, Statement object, Statement body) {
super(loc);
this.varLocation = varLocation;
this.label = label;
this.isDeclaration = isDecl;
this.varName = varName;
this.iterable = object;
this.body = body;
}
}

41
src/java/me/topchetoeu/jscript/compilation/parsing/Parsing.java
View File

@ -1777,6 +1777,46 @@ public class Parsing {
return ParseRes.res(new ForInStatement(loc, nameLoc, labelRes.result, isDecl, nameRes.result, varVal, objRes.result, bodyRes.result), n);
}
public static ParseRes<ForOfStatement> parseForOf(Filename filename, List<Token> tokens, int i) {
var loc = getLoc(filename, tokens, i);
int n = 0;
var labelRes = parseLabel(tokens, i + n);
var isDecl = false;
n += labelRes.n;
if (!isIdentifier(tokens, i + n++, "for")) return ParseRes.failed();
if (!isOperator(tokens, i + n++, Operator.PAREN_OPEN)) return ParseRes.error(loc, "Expected a open paren after 'for'.");
if (isIdentifier(tokens, i + n, "var")) {
isDecl = true;
n++;
}
var nameRes = parseIdentifier(tokens, i + n);
if (!nameRes.isSuccess()) return ParseRes.error(loc, "Expected a variable name for 'for' loop.");
var nameLoc = getLoc(filename, tokens, i + n);
n += nameRes.n;
if (!isIdentifier(tokens, i + n++, "of")) {
if (nameRes.result.equals("const")) return ParseRes.error(loc, "'const' declarations are not supported.");
else if (nameRes.result.equals("let")) return ParseRes.error(loc, "'let' declarations are not supported.");
else return ParseRes.error(loc, "Expected 'of' keyword after variable declaration.");
}
var objRes = parseValue(filename, tokens, i + n, 0);
if (!objRes.isSuccess()) return ParseRes.error(loc, "Expected a value.", objRes);
n += objRes.n;
if (!isOperator(tokens, i + n++, Operator.PAREN_CLOSE)) return ParseRes.error(loc, "Expected a closing paren after for.");
var bodyRes = parseStatement(filename, tokens, i + n);
if (!bodyRes.isSuccess()) return ParseRes.error(loc, "Expected a for body.", bodyRes);
n += bodyRes.n;
return ParseRes.res(new ForOfStatement(loc, nameLoc, labelRes.result, isDecl, nameRes.result, objRes.result, bodyRes.result), n);
}
public static ParseRes<TryStatement> parseCatch(Filename filename, List<Token> tokens, int i) {
var loc = getLoc(filename, tokens, i);
int n = 0;
@ -1833,6 +1873,7 @@ public class Parsing {
parseSwitch(filename, tokens, i),
parseFor(filename, tokens, i),
parseForIn(filename, tokens, i),
parseForOf(filename, tokens, i),
parseDoWhile(filename, tokens, i),
parseCatch(filename, tokens, i),
parseCompound(filename, tokens, i),