On 2021-03-21 00:24, Revar Desmera wrote:
Here’s my first pass thoughts on an immutable table/dictionary data
type for OpenSCAD:
// Dictionary declaration.
a = "fee"; b = "fie";
dict1 = {
"foo": 23, // KEY : VALUE
"bar": 77, // String keys.
false: a, // Boolean keys.
99 : 34, // Numeric keys.
56 : "AZ", // Value can be any type.
"baz": 19, // Should lists, ranges, or functions be allowed
for keys?
"bar": 65, // Overwrite previous key entry.
undef: 77, // Should undef keys be allowed?
"bla": undef, // Should undef values be allowed?
str("c","a","t") : b // Expressions usable for keys or values.
};
For what it is worth, most languages have these kind of look-up tables.
AngelCAD has both 'map' and 'dictionary':
A 'map' is a look-up table where the key and value types can be
anything, but all the entries have the same key and value types:
// type-safe map of integers
map<string,int> dict1;
dict1.insert("foo",23);
dict1.insert("bar",77);
Since geometric objects also have types, you can include them in a map.
If the abstract shape@ type is used in the declaration, you can have a
mixture of 2d or 3d objects in the same map (the @ denotes a handle):
// type-safe map of abstract 2d or 3d shapes
map<string,shape@> dict2;
dict2.insert("sphere",sphere(33));
dict2.insert("circle",circle(50));
A slightly different look-up table is the 'dictionary' type, which uses
only strings as keys, but the value type can be anything and can vary
between entries in the dictionary:
// dictionary of mixed types
dictionary dict3 = {
{"foo", 23}
,{"bar", 77}
,{"sphere", @sphere(33)}
,{"circle", @circle(50)}
};
Personally, I find the map more useful than dictionary.
Carsten Arnholm
On 2021-03-21 00:24, Revar Desmera wrote:
> Here’s my first pass thoughts on an immutable table/dictionary data
> type for OpenSCAD:
>
>> // Dictionary declaration.
>> a = "fee"; b = "fie";
>> dict1 = {
>> "foo": 23, // KEY : VALUE
>> "bar": 77, // String keys.
>> false: a, // Boolean keys.
>> 99 : 34, // Numeric keys.
>> 56 : "AZ", // Value can be any type.
>> "baz": 19, // Should lists, ranges, or functions be allowed
>> for keys?
>> "bar": 65, // Overwrite previous key entry.
>> undef: 77, // Should undef keys be allowed?
>> "bla": undef, // Should undef values be allowed?
>> str("c","a","t") : b // Expressions usable for keys or values.
>> };
For what it is worth, most languages have these kind of look-up tables.
AngelCAD has both 'map' and 'dictionary':
A 'map' is a look-up table where the key and value types can be
anything, but all the entries have the same key and value types:
// type-safe map of integers
map<string,int> dict1;
dict1.insert("foo",23);
dict1.insert("bar",77);
Since geometric objects also have types, you can include them in a map.
If the abstract shape@ type is used in the declaration, you can have a
mixture of 2d or 3d objects in the same map (the @ denotes a handle):
// type-safe map of abstract 2d or 3d shapes
map<string,shape@> dict2;
dict2.insert("sphere",sphere(33));
dict2.insert("circle",circle(50));
A slightly different look-up table is the 'dictionary' type, which uses
only strings as keys, but the value type can be anything and can vary
between entries in the dictionary:
// dictionary of mixed types
dictionary dict3 = {
{"foo", 23}
,{"bar", 77}
,{"sphere", @sphere(33)}
,{"circle", @circle(50)}
};
Personally, I find the map more useful than dictionary.
Carsten Arnholm
