12. A computer-readable medium containing instructions for causing a computer system select an operand for an operator during data entry of the nodes of an intentional program tree, the intentional program tree having nodes representing high-level computational constructs, by: receiving a sequence of tokens, each token indicating a computational construct corresponding to a node of the intentional program tree; when a received token represents an operator, identifying an operand of the operator according to predefined rules of operator precedence so long as no portion of the intentional program tree is currently selected; and adding a node to the intentional program tree indicating the operator with the identified operand.
12. A computer-readable medium containing instructions for causing a computer system select an operand for an operator during data entry of the nodes of an intentional program tree, the intentional program tree having nodes representing high-level computational constructs, by: receiving a sequence of tokens, each token indicating a computational construct corresponding to a node of the intentional program tree; when a received token represents an operator, identifying an operand of the operator according to predefined rules of operator precedence so long as no portion of the intentional program tree is currently selected; and adding a node to the intentional program tree indicating the operator with the identified operand. 13. The computer-readable medium of claim 12 wherein the predefined rules of operator precedence are in accordance with the C programming language.