Focal is an interpreted language like basic designed for quickly and easily writing program. It dates from the late 1960's. A description of Focal and tutorial on using it: Introduction to Focal 1969 promotional handout (Douglas W. Jones).
The following is the online help that came with the OMSI Focal 71
WHILE WRITING A PROGRAM, YOU MAY ASK 'HELP' TO REVIEW SECTIONS,
PHRASES, WORDS OR SYMBOLS LISTED BELOW BY GIVING THE DIRECT COMMAND ---
'L G HELP'. SHOULD YOU WISH TO RETURN TO YOUR PROGRAM BEFORE HELP'S
RESPONSE IS DONE, HOLD DOWN THE 'CTRL' KEY WHILE STRIKING THE
'P' --- THEN TYPE 'G' AND HIT 'RETURN'.
INDEX FOR 'HELP' --- PS/8 FOCAL, 1971
COMMANDS SYMBOLS FUNCTIONS
-------------------- -------------------- --------------------
FABS( ) ABSOLUTE VALUE
ELEMENTARY COMMANDS ARITHMETIC SYMBOLS FADC( ) ANALOG-DIGITAL
-------------------- -------------------- FATN( ) ARCTANGENT
FCOS( ) COSINE
ASK ^ EXPONENTIATION FDIS( ) DISPLAY
COMMENT * MULTIPLICATION FEXP( ) EXPONENTIAL
CONTINUE / DIVISION FITR( ) INTEGER
DO + ADDITION FLOG( ) LOG (BASE E)
ERASE - SUBTRACTION FRAN( ) RANDOM NUMBER
FOR () PARENTHESES FSGN( ) SIGN PART
GO [] SQUARE BRACKETS FSIN( ) SINE
GOTO <> ANGLE BRACKETS FSQT( ) SQUARE ROOT
IF FIN( ) CHARACTER INPUT
MODIFY FOUT( ) CHARACTER OUTPUT
QUIT SPECIAL CHARACTERS
RETURN --------------------
SET
TYPE ! RETURN/LINE FEED MISCELLANEOUS
WRITE # CARRIAGE RETURN --------------------
: TAB
% OUTPUT FORMATTER CHANGES FROM FOCAL 69
LIBRARY COMMANDS $ SYMBOL TABLE DEVICE NAMES
-------------------- " QUOTATION MARKS DIRECT COMMANDS
? TRACE ERROR CODES
LIBRARY CALL E POWER-OF-TEN [&] EXPRESSIONS
LIBRARY DELETE RUBOUT KEY FILES
LIBRARY GOSUB CTRL/C HIGH SPEED READER
LIBRARY LIST CTRL/G [BELL] INDIRECT COMMANDS
LIBRARY RUN CTRL/L INITIAL DIALOGUE
LIBRARY SAVE CTRL/P (Stop Run) LINE NUMBERS
LIBRARY EXIT CTRL/Z MERGING PROGRAMS
LINE FEED KEY NAMES OF FILES
_ KILL LINE PRECISION
FILE COMMANDS RETURN KEY PIP
-------------------- ALT MODE KEY PUSHDOWN LIST OVERFLOW
SPACE KEY SAMPLE FILES PROGRAM
OPEN INPUT , COMMA SIZE OF PROGRAMS
OPEN OUTPUT ; SEMICOLON STRINGS
OPEN RESTORE INPUT SUBSCRIPTING
OPEN RESTORE OUTPUT SUMMARY OF COMMANDS
OUTPUT CLOSE TAB
EXAMPLE VARIABLES
(A COPY OF THE 'HELP' PROGRAM IS SAVED UNDER THE NAME 'HELP.RE')
Example of running help
Help on other languages and links to main help
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