Pico Versions

There are currently two "official" versions of Pico: Pico 1.0 and Pico 2.0. Although Pico 2.0 is more stable, much faster, and more advanced than Pico 1.0, we still keep Pico1.0 alive because of the tremendous amount of courseware that was developed with it. We currently simply do not have the resources to change all those transparancies overnight.

This Site

This site was majorly developed with Pico 2.0 in mind. All the screen shots were made in Pico 2.0. The only sections that are still in Pico 1.0 are

• The courseware section. All transparancies are about Pico 1.0.
• The downloads section mentions both versions.
• The meta circular evaluator section (The Anatomy of Pico) belongs to the courseware. Hence it is also in Pico 1.0.

Differences

Apart from big differences in the implementation (whose dissection is also a big part of our courseware!) from a programmer's point of view, the differences between Pico1.0 and Pico2.0 are:

• Pico 2.0 has first class dictionaries, and a dot notation to qualify them.
• There is a slight difference in natives. E.g. Pico 1.0 uses and while Pico 2.0 uses & for logical and predicate.
• Pico 2.0 features first class continuations, while Pico 1.0 doesn't
• Symbols are not supported by Pico 1.0
• Pico 2.0 has special multidimensional table syntax
• Pico 2.0 makes a difference between definition and declaration. Pico 1.0 does not.