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The Squeak Language stated semi-formally

The following more or less formal specification of the Squeak Language is derived from an  EBNF definition of Squeak 2.7alpha by - Dwight Hughes. It comes from the Swiki, and  should be considered only a snapshot of Squeak at this version. 

By "EBNF" is meant "Extended Backus-Naur Formalism". This is a way to write formal grammars widely used in linguistics (and elsewhere) and is named after its originators.

The EBNF used here is defined as:

[ ... ] apply zero or one times;
[ ... ]* apply zero or more times;
[ ... ]+ apply one or more times;
... | ... choose one of the alternatives;
"..." use the literal characters enclosed; 
( ... ) used for grouping.

In what follows the defined terms are set in bold-face red, and  I divide the specification in some convenient groups, namely

1. Letters and digits
2. Interpunctions
3.1: Terms: Variable identifiers of various kinds
3.2: Terms: Arrays
3.3: Terms: Numerical terms
3.4: Terms: Logical Constants
3.7: Terms:  Logical Variables
4. Statements 

This sequence works from the smallest and simplest expressions  in Squeak (letters and digits) to the longest and most complex expressions in Squeak (methods, messages, blocks).

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