diff options
| -rw-r--r-- | MLKInterpreter.m | 52 |
1 files changed, 28 insertions, 24 deletions
diff --git a/MLKInterpreter.m b/MLKInterpreter.m index f4718e8..9871cfa 100644 --- a/MLKInterpreter.m +++ b/MLKInterpreter.m @@ -60,6 +60,19 @@ #endif +#define RETURN_VALUE(thing) \ +{ return [NSArray arrayWithObject:nullify(thing)]; } + +static id +PRIMARY (id array) +{ + if ([array count] > 0) + return [array objectAtIndex:0]; + else + return nil; +} + + @implementation MLKInterpreter +(void) initialize { @@ -68,10 +81,9 @@ +(id) compile:(id)object inContext:(MLKLexicalContext *)context { - return [[self eval:object - inLexicalContext:context - withEnvironment:[MLKLexicalEnvironment globalEnvironment]] - objectAtIndex:0]; + return PRIMARY ([self eval:object + inLexicalContext:context + withEnvironment:[MLKLexicalEnvironment globalEnvironment]]); } +(NSArray*) eval:(id)program @@ -159,10 +171,6 @@ @end -#define RETURN_VALUE(thing) \ -{ return [NSArray arrayWithObject:nullify(thing)]; } - - @implementation MLKForm (MLKInterpretation) -(NSArray *) interpret { @@ -243,7 +251,7 @@ NSArray *values; MLKDynamicContext *newctx; - catchTag = [[_tagForm interpretWithEnvironment:env] objectAtIndex:0]; + catchTag = PRIMARY ([_tagForm interpretWithEnvironment:env]); NS_DURING { @@ -335,7 +343,7 @@ @implementation MLKIfForm (MLKInterpretation) -(NSArray *) reallyInterpretWithEnvironment:(MLKLexicalEnvironment *)env { - id cndval = denullify([[_conditionForm interpretWithEnvironment:env] objectAtIndex:0]); + id cndval = denullify(PRIMARY([_conditionForm interpretWithEnvironment:env])); if (cndval) return [_consequentForm interpretWithEnvironment:env]; else @@ -420,9 +428,8 @@ for (i = 0; i < [_variableBindingForms count]; i++) { id variable = [[_variableBindingForms objectAtIndex:i] name]; - id value = [[[_variableBindingForms objectAtIndex:i] - interpretWithEnvironment:env] - objectAtIndex:0]; + id value = PRIMARY([[_variableBindingForms objectAtIndex:i] + interpretWithEnvironment:env]); if ([_bodyContext variableIsLexical:variable]) { [newenv addValue:value forSymbol:variable]; @@ -481,7 +488,7 @@ { NSMutableArray *results = [NSMutableArray array]; int i; - id <MLKFuncallable> function = [[_functionForm interpretWithEnvironment:env] objectAtIndex:0]; + id <MLKFuncallable> function = PRIMARY ([_functionForm interpretWithEnvironment:env]); for (i = 0; i < [_bodyForms count]; i++) { @@ -521,10 +528,8 @@ @implementation MLKProgVForm (MLKInterpretation) -(NSArray *) reallyInterpretWithEnvironment:(MLKLexicalEnvironment *)env { - id variables = [[_variableListForm interpretWithEnvironment:env] - objectAtIndex:0]; - id values = [[_valueListForm interpretWithEnvironment:env] - objectAtIndex:0]; + id variables = PRIMARY([_variableListForm interpretWithEnvironment:env]); + id values = PRIMARY([_valueListForm interpretWithEnvironment:env]); MLKDynamicContext *dynctx; id result; @@ -581,7 +586,7 @@ NSArray *values; NSDictionary *userInfo; - catchTag = [[_tagForm interpretWithEnvironment:env] objectAtIndex:0]; + catchTag = PRIMARY([_tagForm interpretWithEnvironment:env]); values = [_valueForm interpretWithEnvironment:env]; userInfo = [NSDictionary dictionaryWithObjectsAndKeys: @@ -641,9 +646,8 @@ for (i = 0; i < [_argumentForms count]; i++) { - id result = [[[_argumentForms objectAtIndex:i] - interpretWithEnvironment:env] - objectAtIndex:0]; + id result = PRIMARY([[_argumentForms objectAtIndex:i] + interpretWithEnvironment:env]); [args addObject:result]; } @@ -687,7 +691,7 @@ for (i = 0; i < [_variables count]; i++) { id symbol = denullify([_variables objectAtIndex:i]); - value = [[[_valueForms objectAtIndex:i] interpretWithEnvironment:env] objectAtIndex:0]; + value = PRIMARY([[_valueForms objectAtIndex:i] interpretWithEnvironment:env]); if ([_context variableIsLexical:symbol]) [env setValue:value forSymbol:symbol]; @@ -713,7 +717,7 @@ for (i = 0; i < [_functionNames count]; i++) { id symbol = denullify([_functionNames objectAtIndex:i]); - value = [[[_valueForms objectAtIndex:i] interpretWithEnvironment:env] objectAtIndex:0]; + value = PRIMARY([[_valueForms objectAtIndex:i] interpretWithEnvironment:env]); if ([_context symbolNamesFunction:symbol]) { |