json

{
  "engine": "BASIC++",
  "version": "6.5.2",
  "edition": "Standard & Lite Unified",
  "license": "Copyleft (c) 2026 BASIC++ Community",
  "total_keywords": 116,
  "keywords": [
    {
      "name": "RND",
      "category": "Math Functions",
      "syntax": "RND[(x)]",
      "help_text": "Returns a double-precision pseudo-random number in range [0.0, 1.0). If x < 0, seeds generator.",
      "error_codes": "Error 13: Type Mismatch (non-numeric argument)"
    },
    {
      "name": "INT",
      "category": "Math Functions",
      "syntax": "INT(x)",
      "help_text": "Returns the largest integer less than or equal to x (floor conversion).",
      "error_codes": "Error 13: Type Mismatch (INT expects one numeric argument)"
    },
    {
      "name": "ABS",
      "category": "Math Functions",
      "syntax": "ABS(x)",
      "help_text": "Returns the absolute value of a numeric expression.",
      "error_codes": "Error 13: Type Mismatch (ABS expects one numeric argument)"
    },
    {
      "name": "SQR",
      "category": "Math Functions",
      "syntax": "SQR(x)",
      "help_text": "Returns the non-negative square root of a numeric expression x >= 0.",
      "error_codes": "Error 5: Illegal Function Call (SQR of negative number), Error 13: Type Mismatch (SQR expects one numeric argument)"
    },
    {
      "name": "SIN",
      "category": "Math Functions",
      "syntax": "SIN(radians)",
      "help_text": "Returns the trigonometric sine of an angle given in radians.",
      "error_codes": "Error 13: Type Mismatch (SIN expects one numeric argument)"
    },
    {
      "name": "COS",
      "category": "Math Functions",
      "syntax": "COS(radians)",
      "help_text": "Returns the trigonometric cosine of an angle given in radians.",
      "error_codes": "Error 13: Type Mismatch (COS expects one numeric argument)"
    },
    {
      "name": "TAN",
      "category": "Math Functions",
      "syntax": "TAN(radians)",
      "help_text": "Returns the trigonometric tangent of an angle given in radians.",
      "error_codes": "Error 13: Type Mismatch (TAN expects one numeric argument)"
    },
    {
      "name": "ATN",
      "category": "Math Functions",
      "syntax": "ATN(x)",
      "help_text": "Returns the arctangent of a numeric expression in radians.",
      "error_codes": "Error 13: Type Mismatch (ATN expects one numeric argument)"
    },
    {
      "name": "LOG",
      "category": "Math Functions",
      "syntax": "LOG(x)",
      "help_text": "Returns the natural logarithm (base e) of a numeric expression x > 0.",
      "error_codes": "Error 5: Illegal Function Call (LOG of zero or negative number), Error 13: Type Mismatch (LOG expects one numeric argument)"
    },
    {
      "name": "EXP",
      "category": "Math Functions",
      "syntax": "EXP(x)",
      "help_text": "Returns e raised to the power of a numeric expression x.",
      "error_codes": "Error 6: Overflow (EXP exponent too large), Error 13: Type Mismatch (EXP expects one numeric argument)"
    },
    {
      "name": "ACOS",
      "category": "Math Functions",
      "syntax": "ACOS(x)",
      "help_text": "Returns the arccosine of x in radians for -1.0 <= x <= 1.0.",
      "error_codes": "Error 5: Illegal Function Call (ACOS argument out of range [-1, 1]), Error 13: Type Mismatch (ACOS expects one numeric argument)"
    },
    {
      "name": "ASIN",
      "category": "Math Functions",
      "syntax": "ASIN(x)",
      "help_text": "Returns the arcsine of x in radians for -1.0 <= x <= 1.0.",
      "error_codes": "Error 5: Illegal Function Call (ASIN argument out of range [-1, 1]), Error 13: Type Mismatch (ASIN expects one numeric argument)"
    },
    {
      "name": "ATAN2",
      "category": "Math Functions",
      "syntax": "ATAN2(y, x)",
      "help_text": "Returns the 2-argument arctangent of y and x in radians.",
      "error_codes": "Error 13: Type Mismatch (ATAN2 expects two numeric arguments)"
    },
    {
      "name": "CEIL",
      "category": "Math Functions",
      "syntax": "CEIL(x)",
      "help_text": "Returns the smallest integer greater than or equal to x.",
      "error_codes": "Error 13: Type Mismatch (CEIL expects one numeric argument)"
    },
    {
      "name": "CLAMP",
      "category": "Math Functions",
      "syntax": "CLAMP(val, min_val, max_val)",
      "help_text": "Clamps a value to be within the range [min_val, max_val].",
      "error_codes": "Error 13: Type Mismatch (CLAMP expects three numeric arguments)"
    },
    {
      "name": "FIX",
      "category": "Math Functions",
      "syntax": "FIX(x)",
      "help_text": "Returns the truncated integer part of x (truncates towards zero).",
      "error_codes": "Error 13: Type Mismatch (FIX expects one numeric argument)"
    },
    {
      "name": "FLOOR",
      "category": "Math Functions",
      "syntax": "FLOOR(x)",
      "help_text": "Returns the largest integer less than or equal to x.",
      "error_codes": "Error 13: Type Mismatch (FLOOR expects one numeric argument)"
    },
    {
      "name": "LERP",
      "category": "Math Functions",
      "syntax": "LERP(a, b, t)",
      "help_text": "Performs linear interpolation between a and b using weight t (a + (b - a) * t).",
      "error_codes": "Error 13: Type Mismatch (LERP expects three numeric arguments)"
    },
    {
      "name": "PI",
      "category": "Math Functions",
      "syntax": "PI()",
      "help_text": "Returns the mathematical constant pi (~3.141592653589793).",
      "error_codes": "Error 5: Illegal Function Call (PI expects 0 arguments)"
    },
    {
      "name": "ROUND",
      "category": "Math Functions",
      "syntax": "ROUND(x [, decimals])",
      "help_text": "Rounds a numeric expression x to the specified number of decimal places (default 0).",
      "error_codes": "Error 13: Type Mismatch (ROUND expects 1 or 2 numeric arguments)"
    },
    {
      "name": "SGN",
      "category": "Math Functions",
      "syntax": "SGN(x)",
      "help_text": "Returns the sign of x: 1 if x > 0, 0 if x = 0, -1 if x < 0.",
      "error_codes": "Error 13: Type Mismatch (SGN expects one numeric argument)"
    },
    {
      "name": "BIN$",
      "category": "String Functions",
      "syntax": "BIN$(x)",
      "help_text": "Returns the binary string representation of integer x.",
      "error_codes": "Error 13: Type Mismatch (BIN$ expects one numeric argument)"
    },
    {
      "name": "CHR$",
      "category": "String Functions",
      "syntax": "CHR$(code)",
      "help_text": "Returns a 1-character string containing the character corresponding to ASCII code (0-255).",
      "error_codes": "Error 5: Illegal Function Call (code out of range 0-255), Error 13: Type Mismatch (CHR$ expects one numeric argument)"
    },
    {
      "name": "HEX$",
      "category": "String Functions",
      "syntax": "HEX$(x)",
      "help_text": "Returns the hexadecimal string representation of integer x.",
      "error_codes": "Error 13: Type Mismatch (HEX$ expects one numeric argument)"
    },
    {
      "name": "INSTR",
      "category": "String Functions",
      "syntax": "INSTR([start,] str$, match$)",
      "help_text": "Returns the 1-based position of the first occurrence of match$ in str$. Returns 0 if not found.",
      "error_codes": "Error 5: Illegal Function Call (start <= 0), Error 13: Type Mismatch (expects string arguments)"
    },
    {
      "name": "LCASE$",
      "category": "String Functions",
      "syntax": "LCASE$(str$)",
      "help_text": "Returns a copy of str$ with all uppercase letters converted to lowercase.",
      "error_codes": "Error 13: Type Mismatch (LCASE$ expects one string argument)"
    },
    {
      "name": "LEFT$",
      "category": "String Functions",
      "syntax": "LEFT$(str$, n)",
      "help_text": "Returns the leftmost n characters of str$.",
      "error_codes": "Error 5: Illegal Function Call (n < 0), Error 13: Type Mismatch (LEFT$ expects string and numeric arguments)"
    },
    {
      "name": "LEN",
      "category": "String Functions",
      "syntax": "LEN(str$)",
      "help_text": "Returns the number of characters in str$.",
      "error_codes": "Error 13: Type Mismatch (LEN expects one string argument)"
    },
    {
      "name": "LTRIM$",
      "category": "String Functions",
      "syntax": "LTRIM$(str$)",
      "help_text": "Returns a copy of str$ with leading whitespace removed.",
      "error_codes": "Error 13: Type Mismatch (LTRIM$ expects one string argument)"
    },
    {
      "name": "MID$",
      "category": "String Functions",
      "syntax": "MID$(str$, start [, length])",
      "help_text": "Returns a substring of str$ starting at 1-based index start for length characters.",
      "error_codes": "Error 5: Illegal Function Call (start <= 0 or length < 0), Error 13: Type Mismatch (MID$ argument type error)"
    },
    {
      "name": "OCT$",
      "category": "String Functions",
      "syntax": "OCT$(x)",
      "help_text": "Returns the octal string representation of integer x.",
      "error_codes": "Error 13: Type Mismatch (OCT$ expects one numeric argument)"
    },
    {
      "name": "PACK$",
      "category": "String Functions",
      "syntax": "PACK$(fmt$, val1 [, val2, ...])",
      "help_text": "Packs binary data values into a binary string according to format template fmt$.",
      "error_codes": "Error 5: Illegal Function Call (invalid format character), Error 13: Type Mismatch (expects string format)"
    },
    {
      "name": "RIGHT$",
      "category": "String Functions",
      "syntax": "RIGHT$(str$, n)",
      "help_text": "Returns the rightmost n characters of str$.",
      "error_codes": "Error 5: Illegal Function Call (n < 0), Error 13: Type Mismatch (RIGHT$ expects string and numeric arguments)"
    },
    {
      "name": "RTRIM$",
      "category": "String Functions",
      "syntax": "RTRIM$(str$)",
      "help_text": "Returns a copy of str$ with trailing whitespace removed.",
      "error_codes": "Error 13: Type Mismatch (RTRIM$ expects one string argument)"
    },
    {
      "name": "SPACE$",
      "category": "String Functions",
      "syntax": "SPACE$(n)",
      "help_text": "Returns a string consisting of n space characters.",
      "error_codes": "Error 5: Illegal Function Call (n < 0), Error 13: Type Mismatch (SPACE$ expects one numeric argument)"
    },
    {
      "name": "STR$",
      "category": "String Functions",
      "syntax": "STR$(x)",
      "help_text": "Returns the string representation of numeric expression x.",
      "error_codes": "Error 13: Type Mismatch (STR$ expects one numeric argument)"
    },
    {
      "name": "STRING$",
      "category": "String Functions",
      "syntax": "STRING$(n, char_spec)",
      "help_text": "Returns a string of n repeating characters specified by ASCII code or 1st char of string.",
      "error_codes": "Error 5: Illegal Function Call (n < 0), Error 13: Type Mismatch (STRING$ argument type error)"
    },
    {
      "name": "TRIM$",
      "category": "String Functions",
      "syntax": "TRIM$(str$)",
      "help_text": "Returns a copy of str$ with both leading and trailing whitespace removed.",
      "error_codes": "Error 13: Type Mismatch (TRIM$ expects one string argument)"
    },
    {
      "name": "UCASE$",
      "category": "String Functions",
      "syntax": "UCASE$(str$)",
      "help_text": "Returns a copy of str$ with all lowercase letters converted to uppercase.",
      "error_codes": "Error 13: Type Mismatch (UCASE$ expects one string argument)"
    },
    {
      "name": "UNPACK",
      "category": "String Functions",
      "syntax": "UNPACK(fmt$, bin_str$)",
      "help_text": "Unpacks binary data from bin_str$ according to format template fmt$.",
      "error_codes": "Error 5: Illegal Function Call (invalid format character), Error 13: Type Mismatch (expects string arguments)"
    },
    {
      "name": "VAL",
      "category": "String Functions",
      "syntax": "VAL(str$)",
      "help_text": "Returns the numeric value represented by string str$. Returns 0 if str$ is not a valid number.",
      "error_codes": "Error 13: Type Mismatch (VAL expects one string argument)"
    },
    {
      "name": "BITCOUNT",
      "category": "Bitwise Functions",
      "syntax": "BITCOUNT(x)",
      "help_text": "Returns the number of set bits (population count) in integer x.",
      "error_codes": "Error 13: Type Mismatch (BITCOUNT expects one numeric argument)"
    },
    {
      "name": "READBIT",
      "category": "Bitwise Functions",
      "syntax": "READBIT(val, bit_pos)",
      "help_text": "Returns the bit value (0 or 1) at bit_pos (0-63) of integer val.",
      "error_codes": "Error 5: Illegal Function Call (bit_pos out of range 0-63), Error 13: Type Mismatch (expects numeric arguments)"
    },
    {
      "name": "RESETBIT",
      "category": "Bitwise Functions",
      "syntax": "RESETBIT(val, bit_pos)",
      "help_text": "Returns val with the bit at bit_pos (0-63) cleared to 0.",
      "error_codes": "Error 5: Illegal Function Call (bit_pos out of range 0-63), Error 13: Type Mismatch (expects numeric arguments)"
    },
    {
      "name": "SETBIT",
      "category": "Bitwise Functions",
      "syntax": "SETBIT(val, bit_pos)",
      "help_text": "Returns val with the bit at bit_pos (0-63) set to 1.",
      "error_codes": "Error 5: Illegal Function Call (bit_pos out of range 0-63), Error 13: Type Mismatch (expects numeric arguments)"
    },
    {
      "name": "SHL",
      "category": "Bitwise Functions",
      "syntax": "SHL(val, shift_bits)",
      "help_text": "Performs a bitwise left shift on integer val by shift_bits.",
      "error_codes": "Error 5: Illegal Function Call (shift_bits < 0 or >= 64), Error 13: Type Mismatch (expects numeric arguments)"
    },
    {
      "name": "SHR",
      "category": "Bitwise Functions",
      "syntax": "SHR(val, shift_bits)",
      "help_text": "Performs a bitwise right shift on integer val by shift_bits.",
      "error_codes": "Error 5: Illegal Function Call (shift_bits < 0 or >= 64), Error 13: Type Mismatch (expects numeric arguments)"
    },
    {
      "name": "TOGGLEBIT",
      "category": "Bitwise Functions",
      "syntax": "TOGGLEBIT(val, bit_pos)",
      "help_text": "Returns val with the bit at bit_pos (0-63) inverted (toggled).",
      "error_codes": "Error 5: Illegal Function Call (bit_pos out of range 0-63), Error 13: Type Mismatch (expects numeric arguments)"
    },
    {
      "name": "CLOCK",
      "category": "System Functions",
      "syntax": "CLOCK()",
      "help_text": "Returns the current system Unix timestamp in seconds.",
      "error_codes": "Error 5: Illegal Function Call (CLOCK expects 0 arguments)"
    },
    {
      "name": "CLOCK$",
      "category": "System Functions",
      "syntax": "CLOCK$()",
      "help_text": "Returns the current ISO 8601 formatted date/time string (YYYY-MM-DD HH:MM:SS).",
      "error_codes": "Error 5: Illegal Function Call (CLOCK$ expects 0 arguments)"
    },
    {
      "name": "DATE$",
      "category": "System Functions",
      "syntax": "DATE$()",
      "help_text": "Returns the current system date as a string (MM-DD-YYYY).",
      "error_codes": "Error 5: Illegal Function Call (DATE$ expects 0 arguments)"
    },
    {
      "name": "ENVIRON$",
      "category": "System Functions",
      "syntax": "ENVIRON$(var_name$)",
      "help_text": "Returns the value of host environment variable var_name$. Returns empty string if not set.",
      "error_codes": "Error 13: Type Mismatch (ENVIRON$ expects one string argument)"
    },
    {
      "name": "FRE",
      "category": "System Functions",
      "syntax": "FRE(dummy)",
      "help_text": "Returns the number of available free memory bytes in the VM heap.",
      "error_codes": "Error 13: Type Mismatch (FRE expects 1 argument)"
    },
    {
      "name": "INKEY$",
      "category": "System Functions",
      "syntax": "INKEY$()",
      "help_text": "Reads a character non-blockingly from console buffer. Returns empty string if no key pressed.",
      "error_codes": "Error 5: Illegal Function Call (INKEY$ expects 0 arguments)"
    },
    {
      "name": "INP",
      "category": "System Functions",
      "syntax": "INP(port)",
      "help_text": "Reads a byte (0-255) from hardware I/O port address.",
      "error_codes": "Error 5: Illegal Function Call (port out of bounds), Error 13: Type Mismatch (expects numeric port)"
    },
    {
      "name": "PEEK",
      "category": "System Functions",
      "syntax": "PEEK(addr)",
      "help_text": "Reads a byte (0-255) from virtual memory address addr.",
      "error_codes": "Error 5: Illegal Function Call (addr out of memory bounds), Error 13: Type Mismatch (expects numeric address)"
    },
    {
      "name": "TICKS",
      "category": "System Functions",
      "syntax": "TICKS()",
      "help_text": "Returns the number of milliseconds elapsed since system start / platform boot.",
      "error_codes": "Error 5: Illegal Function Call (TICKS expects 0 arguments)"
    },
    {
      "name": "TIME$",
      "category": "System Functions",
      "syntax": "TIME$()",
      "help_text": "Returns the current system time as a string (HH:MM:SS).",
      "error_codes": "Error 5: Illegal Function Call (TIME$ expects 0 arguments)"
    },
    {
      "name": "TIMER",
      "category": "System Functions",
      "syntax": "TIMER()",
      "help_text": "Returns the number of seconds elapsed since midnight.",
      "error_codes": "Error 5: Illegal Function Call (TIMER expects 0 arguments)"
    },
    {
      "name": "GOTO",
      "category": "Control Flow",
      "syntax": "GOTO line_num",
      "help_text": "Unconditionally transfers execution to the specified program line number.",
      "error_codes": "Error 8: Undefined line number (target line does not exist), Error 2: Syntax error (missing line number)"
    },
    {
      "name": "GOSUB",
      "category": "Control Flow",
      "syntax": "GOSUB line_num",
      "help_text": "Pushes current line onto stack and branches execution to specified subroutine line number.",
      "error_codes": "Error 8: Undefined line number (subroutine target missing), Error 2: Syntax error (missing line number)"
    },
    {
      "name": "RETURN",
      "category": "Control Flow",
      "syntax": "RETURN [line_num]",
      "help_text": "Returns control from a GOSUB subroutine to the statement following GOSUB, or specified line.",
      "error_codes": "Error 3: RETURN without GOSUB (call stack empty)"
    },
    {
      "name": "IF",
      "category": "Control Flow",
      "syntax": "IF expr THEN stmt/line [ELSE stmt/line]",
      "help_text": "Evaluates boolean expression expr and executes THEN clause if true, ELSE clause if false.",
      "error_codes": "Error 2: Syntax error (missing THEN or malformed expression)"
    },
    {
      "name": "END",
      "category": "Control Flow",
      "syntax": "END [IF | SUB | FUNCTION | SELECT | STRUCT]",
      "help_text": "Terminates program execution or closes structured block definitions.",
      "error_codes": "Error 2: Syntax error (mismatched block terminator)"
    },
    {
      "name": "REM",
      "category": "Control Flow",
      "syntax": "REM [comment text] or ' [comment text]",
      "help_text": "Defines a remark/comment line ignored by the BASIC engine during execution.",
      "error_codes": "None (comments never generate errors)"
    },
    {
      "name": "STOP",
      "category": "Control Flow",
      "syntax": "STOP",
      "help_text": "Pauses program execution and prints 'Break in line X' message.",
      "error_codes": "None (STOP halts program execution cleanly)"
    },
    {
      "name": "PRINT",
      "category": "Console I/O",
      "syntax": "PRINT [#n,] [exprlist] [;|,]",
      "help_text": "Outputs formatted text or numeric expressions to the console or open file channel.",
      "error_codes": "Error 2: Syntax Error, Error 13: Type Mismatch, Error 52: Bad File Number"
    },
    {
      "name": "INPUT",
      "category": "Console I/O",
      "syntax": "INPUT [;] [\"prompt\"{;|,}] var1[, var2...]",
      "help_text": "Prompts the user or reads values from console input into target variables.",
      "error_codes": "Error 2: Syntax Error, Error 13: Type Mismatch, Error 52: Bad File Number"
    },
    {
      "name": "SELECT",
      "category": "Control Flow",
      "syntax": "SELECT CASE test_expression ... CASE expression_list ... END SELECT",
      "help_text": "Executes one of several blocks of statements depending on the value of an expression.",
      "error_codes": "Error 2: Syntax Error, Error 13: Type Mismatch, Error 37: SELECT Without CASE"
    },
    {
      "name": "FOR",
      "category": "Looping / Control Flow",
      "syntax": "FOR var = start TO end [STEP step]",
      "help_text": "Initiates a counter-controlled loop block executing statements until var reaches end.",
      "error_codes": "Error 2: Syntax Error, Error 13: Type Mismatch, Error 26: FOR Without NEXT"
    },
    {
      "name": "NEXT",
      "category": "Looping / Control Flow",
      "syntax": "NEXT [var1[, var2...]]",
      "help_text": "Increments the FOR loop counter variable and loops back if target bound has not been exceeded.",
      "error_codes": "Error 1: NEXT Without FOR, Error 2: Syntax Error"
    },
    {
      "name": "WHILE",
      "category": "Looping / Control Flow",
      "syntax": "WHILE condition",
      "help_text": "Executes a series of statements in a loop as long as condition evaluates to non-zero (true).",
      "error_codes": "Error 2: Syntax Error, Error 30: WHILE Without WEND"
    },
    {
      "name": "WEND",
      "category": "Looping / Control Flow",
      "syntax": "WEND",
      "help_text": "Terminates a WHILE...WEND loop block and transfers control back to the matching WHILE statement.",
      "error_codes": "Error 29: WEND Without WHILE, Error 2: Syntax Error"
    },
    {
      "name": "DO",
      "category": "Looping / Control Flow",
      "syntax": "DO [{WHILE|UNTIL} condition]",
      "help_text": "Initiates a structured DO...LOOP block, optionally evaluating a WHILE or UNTIL pre-condition.",
      "error_codes": "Error 2: Syntax Error, Error 31: DO Without LOOP"
    },
    {
      "name": "LOOP",
      "category": "Looping / Control Flow",
      "syntax": "LOOP [{WHILE|UNTIL} condition]",
      "help_text": "Terminates a DO...LOOP block, optionally evaluating a post-condition test.",
      "error_codes": "Error 32: LOOP Without DO, Error 2: Syntax Error"
    },
    {
      "name": "EXIT",
      "category": "Looping / Control Flow",
      "syntax": "EXIT {FOR|DO|WHILE|SUB|FUNCTION}",
      "help_text": "Prematurely exits an active loop, SUB, or FUNCTION block.",
      "error_codes": "Error 2: Syntax Error, Error 33: Invalid EXIT Scope"
    },
    {
      "name": "OPEN",
      "category": "Filesystem I/O",
      "syntax": "OPEN filespec [FOR mode] AS [#]file_num [LEN=reclen]",
      "help_text": "Opens a file channel for INPUT, OUTPUT, APPEND, BINARY, or RANDOM I/O operations.",
      "error_codes": "Error 2: Syntax Error, Error 52: Bad File Number, Error 53: File Not Found, Error 55: File Already Open"
    },
    {
      "name": "CLOSE",
      "category": "Filesystem I/O",
      "syntax": "CLOSE [[#]file_num1[, [#]file_num2...]]",
      "help_text": "Closes open file channels, flushing pending I/O buffers to disk.",
      "error_codes": "Error 2: Syntax Error, Error 52: Bad File Number"
    },
    {
      "name": "GET",
      "category": "Filesystem I/O",
      "syntax": "GET [#]file_num [, record_number]",
      "help_text": "Reads a record from a random-access file into the FIELD buffer.",
      "error_codes": "Error 2: Syntax Error, Error 52: Bad File Number, Error 63: Bad Record Number"
    },
    {
      "name": "PUT",
      "category": "Filesystem I/O",
      "syntax": "PUT [#]file_num [, record_number]",
      "help_text": "Writes a record from the FIELD buffer into a random-access file.",
      "error_codes": "Error 2: Syntax Error, Error 52: Bad File Number, Error 63: Bad Record Number"
    },
    {
      "name": "FIELD",
      "category": "Filesystem I/O",
      "syntax": "FIELD [#]file_num, width AS string_var [, width AS string_var...]",
      "help_text": "Allocates space in a random file buffer for record variables.",
      "error_codes": "Error 2: Syntax Error, Error 50: Field Overflow, Error 52: Bad File Number"
    },
    {
      "name": "FILES",
      "category": "Filesystem I/O",
      "syntax": "FILES [filespec]",
      "help_text": "Displays directory listing matching specified file pattern.",
      "error_codes": "Error 2: Syntax Error, Error 53: File Not Found, Error 70: Permission Denied"
    },
    {
      "name": "KILL",
      "category": "Filesystem I/O",
      "syntax": "KILL filespec",
      "help_text": "Deletes specified file from disk storage.",
      "error_codes": "Error 2: Syntax Error, Error 53: File Not Found, Error 70: Permission Denied"
    },
    {
      "name": "MKDIR",
      "category": "Filesystem I/O",
      "syntax": "MKDIR pathspec",
      "help_text": "Creates a new directory on disk.",
      "error_codes": "Error 2: Syntax Error, Error 75: Path/File Access Error, Error 76: Path Not Found"
    },
    {
      "name": "NAME",
      "category": "Filesystem I/O",
      "syntax": "NAME oldspec AS newspec",
      "help_text": "Renames an existing disk file or directory.",
      "error_codes": "Error 2: Syntax Error, Error 53: File Not Found, Error 58: File Already Exists"
    },
    {
      "name": "SEEK",
      "category": "Filesystem I/O",
      "syntax": "SEEK [#]file_num, position",
      "help_text": "Sets the byte offset position for the next read or write operation on an open file.",
      "error_codes": "Error 2: Syntax Error, Error 52: Bad File Number, Error 63: Bad Record Number"
    },
    {
      "name": "SCREEN",
      "category": "Graphics & Display",
      "syntax": "SCREEN mode [, [colorswitch] [, [active_page] [, visual_page]]]",
      "help_text": "Sets text or visual graphics display mode, screen resolution, and active palette pages.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "CLS",
      "category": "Graphics & Display",
      "syntax": "CLS [n]",
      "help_text": "Clears display: CLS -1 (text viewport), CLS -2 (graphics viewport), CLS -3 (full buffer, default), or CLS n (0-15 background color clear).",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "HOME",
      "category": "Graphics & Display",
      "syntax": "HOME [n]",
      "help_text": "Moves text cursor to top-left corner (1, 1) without clearing text screen, optionally changing text color to n (0-15).",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "COLOR",
      "category": "Graphics & Display",
      "syntax": "COLOR [foreground] [, [background] [, border]]",
      "help_text": "Sets active foreground, background, and border display colors.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "LINE",
      "category": "Graphics & Display",
      "syntax": "LINE [[x1, y1]]-(x2, y2) [, [color] [, [B|BF] [, style]]]",
      "help_text": "Draws a straight line or box on the active graphics screen canvas.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "CIRCLE",
      "category": "Graphics & Display",
      "syntax": "CIRCLE (x, y), radius [, [color] [, [start] [, [end] [, aspect]]]]",
      "help_text": "Draws a circle, ellipse, or arc on the active graphics screen canvas.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "SOUND",
      "category": "Sound & Audio",
      "syntax": "SOUND frequency, duration",
      "help_text": "Generates a tone of specified frequency in Hertz for specified duration in clock ticks.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "PLAY",
      "category": "Sound & Audio",
      "syntax": "PLAY command_string",
      "help_text": "Plays musical notes using MML (Music Macro Language) command string.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "BEEP",
      "category": "Sound & Audio",
      "syntax": "BEEP",
      "help_text": "Emits a standard 800 Hz speaker beep tone for 0.25 seconds.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "VOICE",
      "category": "Sound & Audio",
      "syntax": "VOICE channel, waveform, attack, decay, sustain, release",
      "help_text": "Configures synthesizer voice envelope parameters (ADSR) for multi-channel sound output.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "ON KEY",
      "category": "Event Trapping",
      "syntax": "ON KEY(n) GOSUB line_label | KEY(n) {ON|OFF|STOP} | KEY ON | KEY OFF | KEY n, string",
      "help_text": "Establishes an asynchronous interrupt handler for function key presses, or toggles/customizes row 25 function key labels.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "ON TIMER",
      "category": "Event Trapping",
      "syntax": "ON TIMER(seconds) GOSUB line_label | TIMER {ON|OFF|STOP}",
      "help_text": "Establishes a periodic timer interrupt subroutine trigger.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "ON ERROR",
      "category": "Event Trapping",
      "syntax": "ON ERROR GOTO {line_label | 0}",
      "help_text": "Enables error-trapping routine and specifies the first statement of the handler.",
      "error_codes": "Error 2: Syntax Error, Error 5: Illegal Function Call"
    },
    {
      "name": "RESUME",
      "category": "Event Trapping",
      "syntax": "RESUME [0 | NEXT | line_label]",
      "help_text": "Resumes program execution after an error-handling routine finishes.",
      "error_codes": "Error 20: RESUME Without Error, Error 2: Syntax Error"
    },
    {
      "name": "TRY",
      "category": "Event Trapping",
      "syntax": "TRY ... CATCH err_var ... FINALLY ... END TRY",
      "help_text": "Structured exception-handling block supporting TRY, CATCH, FINALLY, and END TRY.",
      "error_codes": "Error 2: Syntax Error, Error 35: TRY Without CATCH/FINALLY"
    },
    {
      "name": "MAT INPUT",
      "category": "Matrix Operations",
      "syntax": "MAT INPUT [#file_num,] array_name [(num_rows [, num_cols])]",
      "help_text": "Reads numeric or string matrix elements from console input or an open file stream.",
      "error_codes": "Error 2: Syntax Error, Error 9: Subscript Out of Range, Error 13: Type Mismatch"
    },
    {
      "name": "MAT PRINT",
      "category": "Matrix Operations",
      "syntax": "MAT PRINT [#file_num,] array_name [;|,]",
      "help_text": "Outputs formatted 1D or 2D matrix array elements to console or file stream.",
      "error_codes": "Error 2: Syntax Error, Error 9: Subscript Out of Range, Error 13: Type Mismatch"
    },
    {
      "name": "MAT READ",
      "category": "Matrix Operations",
      "syntax": "MAT READ array_name [(num_rows [, num_cols])]",
      "help_text": "Populates matrix elements sequentially from DATA statements.",
      "error_codes": "Error 2: Syntax Error, Error 4: Out of DATA, Error 9: Subscript Out of Range"
    },
    {
      "name": "SCOPE",
      "category": "Introspection",
      "syntax": "SCOPE [BEGIN | END | DISABLE kw | ENABLE kw | HOOK ... | MODULE name | PRIVATE sym]",
      "help_text": "Manages lexical scope blocks, keyword enablement, execution hooks, and symbol protection.",
      "error_codes": "Error 2: Syntax Error, Error 13: Permission Denied"
    },
    {
      "name": "HELP",
      "category": "Introspection",
      "syntax": "HELP [keyword | command | block_target]",
      "help_text": "Displays interactive help documentation for statements, functions, syntax, and system components.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "REFORMAT",
      "category": "Program Mgmt & Editing",
      "syntax": "REFORMAT [spaces_per_indent] [target] [CHECK|STRICT|SPLIT|UPPER|LOWER|PRESERVE|SPACES]",
      "help_text": "Reformats BASIC source code with configurable indentation and static structural analysis.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "CHECK",
      "category": "Debug & Testing",
      "syntax": "CHECK [SUMMARY|DETAILED|JSON]",
      "help_text": "Executes static analysis on active program in memory and outputs summary, detailed, or JSON metrics.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "VERIFY",
      "category": "Debug & Testing",
      "syntax": "VERIFY [\"filename.bas\"] [SUMMARY|DETAILED|JSON]",
      "help_text": "Executes static analysis on external disk file or current program in isolated temporary memory.",
      "error_codes": "Error 2: Syntax Error, Error 53: File Not Found"
    },
    {
      "name": "TEST",
      "category": "Debug & Testing",
      "syntax": "TEST \"Suite Name\" | ENDTEST",
      "help_text": "Begins or ends a declarative unit test suite block and outputs assertion metrics.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "DEBUG",
      "category": "Debug & Testing",
      "syntax": "DEBUG [ON|OFF|DUMP|STACK|MEMORY|VARS] | TRACE | TRON | TROFF | BREAK | CONT | BACKTRACE | INFO | DUMP",
      "help_text": "Master interactive debugger control, execution tracing, breakpoint handling, and system introspection suite.",
      "error_codes": "Error 2: Syntax Error, Error 99: Assertion Failed"
    },
    {
      "name": "VERSION",
      "category": "System & Environ",
      "syntax": "VERSION \"1.2.0\" | VER | VER$([target$])",
      "help_text": "Tags or queries active program version metadata and host engine version.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "VARPTR",
      "category": "Variables & Memory",
      "syntax": "VARPTR(var) | VARPTR$(var)",
      "help_text": "Returns the 64-bit integer memory address or descriptor string for a variable.",
      "error_codes": "Error 2: Syntax Error"
    },
    {
      "name": "HOSTNAME",
      "category": "Introspection",
      "syntax": "HOSTNAME",
      "help_text": "Outputs the system hostname to console.",
      "error_codes": "Error 70: Permission Denied"
    },
    {
      "name": "USERNAME",
      "category": "Introspection",
      "syntax": "USERNAME",
      "help_text": "Outputs the current user identity name to console.",
      "error_codes": "Error 70: Permission Denied"
    },
    {
      "name": "SELFTEST",
      "category": "System",
      "syntax": "SELFTEST",
      "help_text": "Executes internal diagnostic suite verifying lexer, memory, string, variable, and array subsystems.",
      "error_codes": "Error 1001-5003: Subsystem Diagnostic Failure"
    }
  ],
  "c_api_layers": [
    {
      "layer": 1,
      "name": "Embedding & Lifecycle",
      "headers": ["bpp_api.h", "boot.h", "vm.h", "config.h"],
      "description": "Core interpreter initialization, script execution, evaluation, and shutdown."
    },
    {
      "layer": 2,
      "name": "Language Core",
      "headers": ["lexer.h", "eval.h", "stmt.h", "types.h", "variables.h", "arrays.h", "strings.h"],
      "description": "Tokenizer, AST evaluation, variables, string pool, and array management."
    },
    {
      "layer": 3,
      "name": "Runtime Extensions",
      "headers": ["file.h", "funcreg.h", "map.h", "struct_ctx.h", "task.h", "metadata.h"],
      "description": "File I/O channels, DEF FN registry, maps, UDT structs, and multitasking."
    },
    {
      "layer": 4,
      "name": "Virtual Devices & I/O",
      "headers": ["vdev.h", "vcon.h", "vfs.h", "vnet.h", "bus.h", "usb.h", "fujinet.h"],
      "description": "Virtual consoles, VFS filesystem abstraction, networking, and hardware bus."
    },
    {
      "layer": 5,
      "name": "Graphics & Sound",
      "headers": ["bgi.h", "bios.h"],
      "description": "Borland Graphics Interface (BGI) rasterizer and authentic IBM PC BIOS emulation."
    },
    {
      "layer": 6,
      "name": "Security & Modules",
      "headers": ["security.h", "module.h"],
      "description": "Capability security sandbox and dynamic C module loading pipeline."
    }
  ]
}