| Grammar Fragment | English Explanation | Formal IL (Allison) | TBIL (Pittman) |
| line::= | Tiny Basic reads lines | GETLINE | GL |
| number | possibly with a line number in front | TSTL <label> | BN <label> |
| -- | insert numbered statement into program | INSERT | IL |
| * | repeat as needed | JMP <label> | BR <label> |
| statement | do whatever the statement rule says to do | STMT: <label> | :STMT |
| is this keyword "PRINT"? | TST S8,'PRINT' | BC SKIP "PR" | |
| expr-list::= | this is what you can print… | -- | |
| string | quoted string | TST S7,'"'; PRS | BC P7 '"'; PQ |
| expression | do the expression evaluation rule | CALL EXPR | JS EXPR |
| -- | print the resulting value | PRN | PN |
| IF | is this keyword "IF"? | TST S9,'IF' | BC INPT "IF" |
| relop | do compare operator rule | CALL RELOP | JS RELO |
| THEN | error if this in not keyword "THEN"? | TST S17,'THEN' | BC I1 "THEN" |
| statement | do whatever the statement rule says to do | JMP STMT | J STMT |
| GOTO | is this keyword "GOTO"? if not, try another | TST S3,'GO'; TST S2,'TO' | BC PRNT "GO"; BC GOSB "TO" |
| expression | do the expression evaluation rule | CALL EXPR | JS EXPR |
| -- | error if not end of statement | DONE | BE * |
| -- | find that line in the program, do it next | XPER | GO |
| LET | is this keyword "LET"? if not, try another | TST S1,'LET' | BC GOTO "LET" |
| var | save variable name; error if none | TSTV S17 | BV * |
| = | error if there is no "=" here | TST S17,'=' | BC * "=" |
| expression | do the expression evaluation rule | CALL EXPR | JS EXPR |
| -- | error if not end of statement | DONE | BE * |
| -- | store the value into the variable | STORE | SV |
| -- | resume with next line | XPER | NX |
Table 1: Partial correlation between Grammar, English pseudocode, and Interpreter Language. Grammar elements in the left column, represented by English pseudocode in the next column, then IL equivalents in the last two columns, Allison's then mine.
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