InModifier.ceylon
import ceylon.ast.core {
InModifier,
Node
}
import com.redhat.ceylon.compiler.typechecker.tree {
JNode=Node,
Tree {
JTypeVariance=TypeVariance
}
}
import com.redhat.ceylon.compiler.typechecker.parser {
CeylonLexer {
in_op=\iIN_OP
}
}
"Converts a RedHat AST [[TypeVariance|JTypeVariance]]
with token type [[`IN_OP`|in_op]]
to a `ceylon.ast` [[InModifier]]."
shared InModifier inModifierToCeylon(JTypeVariance inModifier, Anything(JNode,Node) update = noop) {
"Must be an ‘in’ modifier"
assert (inModifier.mainToken.type == in_op);
value result = InModifier();
update(inModifier, result);
return result;
}
"Compiles the given [[code]] for an In Modifier
into an [[InModifier]] using the Ceylon compiler
(more specifically, the rule for a `variance`)."
shared InModifier? compileInModifier(String code, Anything(JNode,Node) update = noop) {
if (exists jVariance = createParser(code).variance(),
jVariance.mainToken.type == in_op) {
return inModifierToCeylon(jVariance, update);
} else {
return null;
}
}