PILOT Language Reference

PILOT (Programmed Inquiry, Learning Or Teaching) is an educational language from the 1960s, popular on Atari computers. PBXA64 embeds PILOT blocks inside PowerBASIC functions using #PCODE / #ENDP directives.

V10 Feature: PILOT #PCODE blocks are fully lowered to working PowerBASIC code by the compiler. Multiple blocks are supported with block-scoped labels and variables. All PILOT variables are automatically declared as LOCAL for #DIM ALL compatibility.

Command Reference

Command	Description	Example
`T:`	Type (print text)	`T: Hello, World!`
`A:`	Accept (read input)	`A: What is your name?`
`M:`	Match (pattern test)	`M: YES`
`Y:`	Yes branch (match success)	`Y: Correct!`
`N:`	No branch (match failure)	`N: Try again!`
`C:`	Compute (assignment)	`C: score = score + 1`
`J:`	Jump (goto label)	`J: *START`
`U:`	Use (conditional jump/text)	`U: score>=3: *WIN`
`E:`	End (exit PILOT block)	`E:`
`R:`	Remark (comment)	`R: This is a comment`
`S:`	Screen (no-op, accepted)	`S: DRAW 50`
`*LABEL`	Label (jump target)	`*START`

Command

Description

Example

T:

Type (print text)

T: Hello, World!

A:

Accept (read input)

A: What is your name?

M:

Match (pattern test)

M: YES

Y:

Yes branch (match success)

Y: Correct!

N:

No branch (match failure)

N: Try again!

C:

Compute (assignment)

C: score = score + 1

J:

Jump (goto label)

J: *START

U:

Use (conditional jump/text)

U: score>=3: *WIN

E:

End (exit PILOT block)

E:

R:

Remark (comment)

R: This is a comment

S:

Screen (no-op, accepted)

S: DRAW 50

*LABEL

Label (jump target)

*START

PILOT Variables

Variable	Type	Description
`$A`	String	Input from the last `A:` command
`#A`	Numeric	Numeric value of the last `A:` input (via VAL)
`$name`	String	Named string variable (e.g., `$NAME`)
`#count`	Numeric	Named numeric variable (e.g., `#SCORE`)

Variable

Type

Description

$A

String

Input from the last A: command

#A

Numeric

Numeric value of the last A: input (via VAL)

$name

String

Named string variable (e.g., $NAME)

#count

Numeric

Named numeric variable (e.g., #SCORE)

Pattern Matching

Pattern	Match Type	Example
Exact text	Exact match after TRIM$/UCASE$	`M: YES` matches "YES", " yes "
`Y*`	Prefix match	`M: Y*` matches "YES", "YELLOW"
`*ING`	Suffix match	`M: *ING` matches "RUNNING"
`ORL`	Substring match	`M: ORL` matches "WORLD"
`*`	Wildcard (any input)	`M: *` matches anything
Numeric	Exact number match	`M: 42` matches #A = 42
`#VAR`	Numeric variable match	`M: #EXPECTED` matches #A = #EXPECTED
`$VAR`	String variable match	`M: $ANSWER` matches $A = $ANSWER

Pattern

Match Type

Example

Exact text

Exact match after TRIM$/UCASE$

M: YES matches "YES", " yes "

Y*

Prefix match

M: Y* matches "YES", "YELLOW"

*ING

Suffix match

M: *ING matches "RUNNING"

*ORL*

Substring match

M: *ORL* matches "WORLD"

*

Wildcard (any input)

M: * matches anything

Numeric

Exact number match

M: 42 matches #A = 42

#VAR

Numeric variable match

M: #EXPECTED matches #A = #EXPECTED

$VAR

String variable match

M: $ANSWER matches $A = $ANSWER

Example: Quiz Program

FUNCTION PBMAIN() AS LONG #PCODE C: score = 0 *LOOP T: What is 5 + 3? A: M: 8 Y: Correct! $score = $score + 1 N: Wrong! The answer is 8. T: Play again? (YES/NO) A: M: Y* Y: *LOOP T: You got #score correct! E: #ENDP FUNCTION = 0 END FUNCTION

How PILOT Maps to PB

PILOT	Generated PowerBASIC
`T: Hello $name`	`PRINT "Hello "; name$`
`A:`	`INPUT a$ : a# = VAL(a$)`
`M: YES`	`match = (UCASE$(TRIM$(a$)) = "YES")`
`Y: *LABEL`	`IF match THEN GOTO LABEL`
`C: a = b + c`	`a# = b# + c#`
`J: *LABEL`	`GOTO LABEL`
`U: x>=5: *WIN`	`IF x# >= 5 THEN GOTO WIN`
`E:`	`GOTO EndOfPilotBlock`
`*LABEL`	`LABEL:`

PILOT

Generated PowerBASIC

T: Hello $name

PRINT "Hello "; name$

A:

INPUT a$ : a# = VAL(a$)

M: YES

match = (UCASE$(TRIM$(a$)) = "YES")

Y: *LABEL

IF match THEN GOTO LABEL

C: a = b + c

a# = b# + c#

J: *LABEL

GOTO LABEL

U: x>=5: *WIN

IF x# >= 5 THEN GOTO WIN

E:

GOTO EndOfPilotBlock

*LABEL

LABEL:

Multiple Blocks: Multiple #PCODE / #ENDP blocks can appear in a single PB function. Each block gets unique internal prefixes for labels and variables to prevent name collisions.