CSE 2231 – Statement

Your implementation must follow all rules in STATEMENT_MODEL. If your code breaks any rule, the implementation is wrong.

What does StatementKernel modeled by STATEMENT_MODEL mean?

A default BLOCK statement with an empty body: compose((BLOCK, ?, ?), <>)

What does the no-argument constructor new Statement1() create?

STATEMENT_MODEL says test and call are irrelevant when kind is BLOCK — we don't know or care about their values.

Why are the 2nd and 3rd tuple components ? when kind is BLOCK?

Returns the kind/label of the current statement (e.g. BLOCK, IF, WHILE, CALL).

What does this.kind() do?

Inserts statement s at position pos inside a BLOCK statement.

What does addToBlock(int pos, Statement s) do?

Removes and returns the statement at position pos from a BLOCK statement.

What does removeFromBlock(int pos) do?

The number of statements currently inside a BLOCK statement.

What does lengthOfBlock() return?

Builds an IF statement from condition c and body block s. Result: compose((IF, c, ?), )

What does assembleIf(Condition c, Statement s) do?

Breaks apart an IF statement — returns the condition and puts the body block into s. Opposite of assembleIf.

What does disassembleIf(Statement s) do?

addToBlock, removeFromBlock, and lengthOfBlock. Using them on non-BLOCK statements violates STATEMENT_MODEL.

Which methods only work on BLOCK statements?

The abstract mathematical rulebook your implementation must satisfy — defines what each method must do.

What is STATEMENT_MODEL in simple terms?

1st = kind (IF), 2nd = test (condition), 3rd = call (associated call). Body statements are in .

In compose((IF, test, call), ) what do the 3 tuple components represent?

BLOCK is the simplest blank state — IF and WHILE require meaningful test and call values to be valid.

Why does the no-argument constructor default to BLOCK and not IF or WHILE?

s gets replaced with the body block of the IF statement that was disassembled.

What happens to s after calling disassembleIf(Statement s)?

They are inverses — assembleIf builds an IF statement from parts, disassembleIf breaks it back into those parts.

What is the relationship between assembleIf and disassembleIf?