gnu.mapping
Class Location
public abstract class Location
extends java.lang.Object
A Location is an abstract cell/location/variable with a value.
static String | UNBOUND - Magic value used to indicate there is no property binding.
|
UNBOUND
public static final String UNBOUND
Magic value used to indicate there is no property binding.
Location
public Location()
entered
public boolean entered()
True if directly entered in an Environment. (Only if NamedLocation.)
get
public final Object get()
Get the current value of this location.
get
public abstract Object get(Object defaultValue)
getKeyProperty
public Object getKeyProperty()
getKeySymbol
public Symbol getKeySymbol()
getValue
public final Object getValue()
isBound
public boolean isBound()
isConstant
public boolean isConstant()
make
public static Location make(Object init,
String name)
print
public void print(java.io.PrintWriter ps)
set
public abstract void set(Object value)
setRestore
public void setRestore(Object oldValue,
CallContext ctx)
Restore an old value.
oldValue
- the return value from a prior setWithSave.
setValue
public final Object setValue(Object newValue)
setWithSave
public Object setWithSave(Object newValue,
CallContext ctx)
Set a value, but return cookie so old value can be restored.
This is intended for fluid-let where (in the case of multiple threads)
a simple save-restore isn't always the right thing.
toString
public String toString()
undefine
public void undefine()