Class SwitchStatementGenerator

java.lang.Object

org.ek9lang.compiler.phase7.generator.AbstractGenerator

org.ek9lang.compiler.phase7.generator.SwitchStatementGenerator

All Implemented Interfaces:

Function<EK9Parser.SwitchStatementExpressionContext, List<IRInstr>>

public final class SwitchStatementGenerator
extends AbstractGenerator
implements Function<EK9Parser.SwitchStatementExpressionContext, List<IRInstr>>

Generates IR for switch statements and expressions using CONTROL_FLOW_CHAIN. Follows the same pattern as IfStatementGenerator.

Supports both statement and expression forms:

• Statement form: switch expr - no return value
• Expression form: result <- switch expr - returns value assigned to return variable

Current implementation supports: - Literal case comparisons (case 1, case 2, etc.) - Integer type evaluation variable - Default case - Guard variables with all operators (<-, :=, :=?, ?=) - Expression form with ARC-safe result assignment

Preflow handling differs by form:

• Statement form — a guard with a check (<-, :=?, ?=) skips the whole switch when the guard is unset (consistent with WHILE/FOR/TRY), via LoopGuardHelper.evaluateGuardVariable(EK9Parser.PreFlowStatementContext, String) + guard-entry-check wrapping.
• Expression form — a body-skipping guard (<-, :=?, ?=) gates the switch exactly as in statement form (routed through GuardedScopeOrchestrator); the return variable's init is hoisted outside the guard check so the lhs takes it on the skip path. A non-guard preflow (:=, or none) ALWAYS executes and is emitted unconditionally via LoopGuardHelper.evaluatePreFlowSetupOnly(EK9Parser.PreFlowStatementContext) before the switch — it must be emitted, not dropped, or the control expression LOADs an undeclared variable (JVM VerifyError / native empty output).

NOT yet supported: - Enum case comparisons - Multiple literals per case (case 1, 2, 3) - Expression cases (case < 12, case > 50)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final record	SwitchStatementGenerator.EvalVariable	Record to hold evaluation variable information.

Field Summary

Fields inherited from class AbstractGenerator

debugInfoCreator, instructionBuilder, MAX_MESSAGE_LENGTH, stackContext, typeNameOrException

Constructor Summary

Constructors

Constructor	Description
SwitchStatementGenerator(IRGenerationContext stackContext, GeneratorSet generators)

Method Summary

Modifier and Type	Method	Description
List<IRInstr>	apply(EK9Parser.SwitchStatementExpressionContext ctx)

Methods inherited from class AbstractGenerator

addCoverageProbe, createTempVariable, createTempVariableFromContext, extractReturnType, getRecordedSymbolOrException, processBlockStatements, processBlockStatements, truncateMessage, truncateMessage

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface Function

andThen, compose

Constructor Details

SwitchStatementGenerator

public SwitchStatementGenerator(IRGenerationContext stackContext,
 GeneratorSet generators)

Method Details

apply

public List<IRInstr> apply(EK9Parser.SwitchStatementExpressionContext ctx)

Specified by:

apply in interface Function<EK9Parser.SwitchStatementExpressionContext, List<IRInstr>>