Rex Swain's REXX Summary

Reference: http://www.rexswain.com/rexx.html

Rex Swain's REXX Summary

VM/ESA Release 2.1, REXX370 Version 4.00

Last updated 20 October 1998
[Links updated 10 October 2006]

Contents

• Functions
• Syntax
• Symbols
• Operators
• Instructions

See Also

• My REXX Utilities: Various utility programs
• The REXX Language Association
• IBM REXX Manuals on-line
• IBM's REXX Language page
• REXX FAQ by Dave Martin

• Mansfield Software's KEDIT: http://www.kedit.com
  A very nice XEDIT-like editor for Windows that uses REXX as a macro language

• This summary is also available as a Microsoft Word for Windows 95 (version 7.0) document rexx.doc, which will look better when printed. It's formatted for a LaserJet printer, seven 8½×11" pages.

Other Summaries and Demos

• See my home page for other summaries and demos: APL, REXX, KEDIT, XEDIT, Perl, HTML, RGB Colors, HTTP Cookies, Email Forms, CGI Environment Variables, Server Side Includes, etc...

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Functions

bit = ABBREV(information,info[,minlength])     Abbreviation matchnum = ABS(number)                              Absolute valuestr = ADDRESS()                                Query current environmentnum = ARG()                                    Number of argumentsval = ARG(n)                                   Nth argumentbit = ARG(n,'Exists')                          Does nth argument exist?bit = ARG(n,'Omitted')                         Was nth argument omitted?str = BITAND(str1[,[str2][,pad]])              Logically and stringsstr = BITOR(str1[,[str2][,pad]])               Logically or stringsstr = BITXOR(str1[,[str2][,pad]])              Logically xor stringsstr = B2X(str)                                 Binary to hex (0F=00001111)str = CENTER(str,length[,pad])                 Center stringstr = CENTRE(str,length[,pad])                 CENTER for Britsstr = CHARIN([name][,[start][,length]])        Read chars from input streamnum = CHAROUT([name][,[start][,length]])       Write chars to output streambit = CHARS([name])                            Any chars in input stream?bit = CMSFLAG(flag)                            Query SET ... (see CMSFLAG)cix = COMPARE(str1,str2[,pad])                 0 or first mismatchstr = CONDITION('Condition')                   Name of trapped conditionstr = CONDITION(['Instruction'])               CALL or SIGNALstr = CONDITION('Description')                 Description or nullstr = CONDITION('Status')                      ON, OFF, or DELAYstr = COPIES(str,n)                            n copies of entire stringrc  = CSL('rtnname retcode parms')             Callable services librarynum = C2D(str[,n])                             Character to decimalstr = C2X(str)                                 Character to hexadecimalstr = DATATYPE(str)                            NUM or CHARbit = DATATYPE(str,type)                       Matches type? (see DATATYPE)str = DATE()                                   Current date (dd Mmm yyyy)str = DATE(dopt)                               Date info (see DATE)... = DB...(str,...)                           13 DBCS support functionsstr = DELSTR(str,n)                            Delete cix from n to endstr = DELSTR(str,n,length)                     Delete cix n for lengthstr = DELWORD(str,n)                           Delete wix from n to endstr = DELWORD(str,n,length)                    Delete wix n for lengthstr = DIAG(hex[?][,data][,data]...)            ? displays diagnosticsstr = DIAGRC(hex[?][,data][,data]...)          Also returns CP codesstr = D2C(wholenumber[,n])                     Decimal to characterstr = D2X(wholenumber[,n])                     Decimal to hexadecimalstr = ERRORTEXT(n)                             Error message text (0-99)num = EXTERNALS()                              See PARSE EXTERNALwix = FIND(haystack,needle)                    0=not found; prefer WORDPOSstr = FORM()                                   Query NUMERIC FORMstr = FORMAT(num[,[before][,[after]]])         Around decimal placestr = FUZZ()                                   Query NUMERIC FUZZcix = INDEX(haystack,needle[,start])           Default start=1; prefer POSstr = INSERT(new,str[,[n][,[length][,pad]]])   Insert after cix nstr = JUSTIFY(str,length[,pad])                Right-left justifycix = LASTPOS(needle,haystack[,start])         POS from right to leftstr = LEFT(str,length[,pad])                   Take chars from leftnum = LENGTH(str)                              Shape (in chars)str = LINEIN([name][,[line][,count]])          Read line from input streambit = LINEOUT([name][,[string][,line]])        Write line to output streamnum = LINES([name])                            Input stream lines remainingnum = LINESIZE()                               From CP TERM LINESIZEnum = MAX(num[,num...])                        Maximum (up to 10 numbers)num = MIN(num[,num...])                        Minimum (up to 10 numbers)str = OVERLAY(new,str[,[n][,[length][,pad]]])  Overlay after cix ncix = POS(needle,haystack[,startcix])          0=not foundnum = QUEUED()                                 Lines in stacknum = RANDOM()                                 Random whole number 0-999num = RANDOM([min][,[max][,seed]])             Random whole number in rangestr = REVERSE(str)                             Rotate stringstr = RIGHT(str,length[,pad])                  Take chars from rightnum = SIGN(num)                                Signum: -1, 0, or 1num = SOURCELINE()                             Lines in source filestr = SOURCELINE(n)                            Nth line from filestr = SPACE(str[,[n][,pad]])                   Normalize spaces; def n=1hex = STORAGE()                                Virtual storage size in hexhex = STORAGE(address,length)                  Read storagehex = STORAGE(address,length,data)             Write storagestr = STREAM(name[,'State'])                   State of streamstr = STREAM(name,'Description')               State of stream, more detailstr = STREAM(name,'Command',cmd)               Apply command to streamstr = STRIP(str[,[option][,char]])             L, T, or default=Bothstr = SUBSTR(str,firstcix[,[length][,pad]])    Substringstr = SUBWORD(str,firstwix[,length])           Def length=rest of stringstr = SYMBOL(name)                             State: BAD, VAR, or LITstr = TIME()                                   Current time (hh:mm:ss)str = TIME(topt)                               Time info (see TIME)str = TRACE()                                  Query trace actionsstr = TRACE(option)                            Alter trace, return prevstr = TRANSLATE(str[,[new][,[old][,pad]]])     Map old to newnum = TRUNC(num[,n])                           Truncate to n decimalsstr = USERID()                                 Query logon useridval = VALUE(name)                              Query value of nameval = VALUE(name,val)                          Change value of nameval = VALUE(name[,val],selector [groupname])   GLOBAL/LASTING/SESSION varcix = VERIFY(str,okchars[,['Nomatch'],start])  First bad cix; 0=all okcix = VERIFY(str,okchars,'Match'[,start])      First good cix; 0=nonestr = WORD(str,wix)                            Extract nth wordcix = WORDINDEX(str,wix)                       Char pos of nth wordnum = WORDLENGTH(str,wix)                      Chars in nth wordwix = WORDPOS(needle,haystack[,start])         Find word(s)

CMSFLAG(flag)

flag: ABBREV     1=SET ABBREV ON, 0=SET ABBREV OFF      AUTOREAD   1=SET AUTOREAD ON, 0=SET AUTOREAD OFF      CMSTYPE    1=RT or SET CMSTYPE RT, 0=HT or SET CMSTYPE HT      DOS        1=SET DOS ON, 0=SET DOS OFF      EXECTRAC   1=TS or SET EXECTRAC ON, 0=TE or SET EXECTRAC OFF      IMPCP      1=SET IMPCP ON, 0=SET IMPCP OFF      IMPEX      1=SET IMPEX ON, 0=SET IMPEX OFF      PROTECT    1=SET PROTECT ON, 0=SET PROTECT OFF      RELPAGE    1=SET RELPAGE ON, 0=SET RELPAGE OFF      SUBSET     1=SUBSET, 0=RETURNed      XA         1=Running in XA or XC virtual machine, 0=370      XC         1=Running in XC virtual machine, 0=XA or 370      370        1=Running in 370 virtual machine, 0=XA or XC

DATATYPE(str,type)

type: Alphanumeric   Alphanumeric (a-z, A-Z, 0-9)      Binary         Binary (0-1)      C              Mixed SBCS/DBCS string      Dbcs           DBCS-only string enclosed by SO and SI bytes      Lowercase      Lowercase (a-z)      Mixed case     Mixed case (a-z, A-Z)      Number         Number      Symbol         Symbol (valid REXX name)      Uppercase      Uppercase (A-Z)      Whole number   Whole number      heXadecimal    Hexadecimal (a-f, A-F, 0-9)

DATE(dopt)

dopt: Base       Whole days since 1 Jan 0001 (//7 for 0=Monday, 6=Sunday)      Century    Days so far in this century      Days       Days so far in this year      European   dd/mm/yy      Julian     yyddd      Month      Month      Normal     dd Mon yyyy      Ordered    yy/mm/dd      Standard   yyyymmdd      Usa        mm/dd/yy      Weekday    Tuesday

TIME(topt)

topt: Civil      hh:mmxx (1-12, 00-59, am/pm)      Elapsed    sssssssss.uuuuuu (seconds, microseconds)      Hours      Hours since midnight      Long       hh:mm:ss.uuuuuu      Minutes    Minutes since midnight      Normal     hh:mm:ss      Reset      Returns elapsed time, restarts timer      Seconds    Seconds since midnight

Syntax

/* ... */   Comment (may span lines, may be nested),           Line continuation;           Statement separatorv.i         Compound variable'0f'x       Hexadecimal notation'0010'b     Binary notation

Symbols

May use characters: A-Z, a-z, 0-9, and @ # $ \ . ! ? _Special variables: RC, RESULT, SIGL

Operators

Operators are grouped by precedence (highest to lowest) below.
Operators of equal precedence are evaluated from left to right.

\  ¬                Logical NOT (prefix)+                   Numeric (prefix); same as 0+num-                   Negate (prefix); same as 0-num
**                  Raise to (whole) power
*                   Multiply/                   Divide%                   Integer divide: divide and return integer part//                  Remainder: divide and return remainder                      (not modulo; result may be negative)
+                   Add-                   Subtract
(abuttal)  ||       Concatenate without blank(blank)             Concatenate with blank
==                  Strictly equal (identical)¬==  /==  \==       Not strictly equal>>                  Strictly greater than<<                  Strictly less than>>=  ¬<<  \<<       Strictly greater than or equal to; not less than<<=  ¬>>  \>>       Strictly less than or equal to; not greater than=                   Equal (numerically or when padded, etc.)¬=  /=  \=  ><  <>  Not equal; greater than or less than>                   Greater than<                   Less than>=  ¬<  \<          Greater than or equal to; not less than<=  ¬>  \>          Less than or equal to; not greater than
&                   AND
|                   Inclusive OR (either, or both)&&                  Exclusive OR (either, but not both)

Instructions

ADDRESS        Permanently toggle destination of commands to last environmentADDRESS environment        CMS       Full command resolution; default for EXECs        CMSMIXED  Same as CMS but no uppercase translation        COMMAND   Must use EXEC and CP prefixes; most efficient        ''        Same as COMMAND        XEDIT     Route commands to system editor        Permanently change destination of commandsADDRESS VALUE envexpression        Permanently change destination of commandsADDRESS environment cmdexpression        Specify destination for just this one commandARG [template]        Same as PARSE UPPER ARG [template]CALL name [expression [,expression]]...  (up to 20 expressions)        If name in quotes, only built-in or external function called        Optional result returned in special variable RESULTCALL ON condition [NAME trapname]        ERROR     Host command returns non-zero rc                    (or just positive rc if ON FAILURE too)        FAILURE   Host command returns negative return code        HALT      Attempt to interrupt (such as HI)        NOTREADY  Error during input or output operation        Call on specified condition; variable SIGL contains line numberCALL OFF condition        Cancel CALL ON trapDO [ name = expr [TO expr] [BY expr] [FOR expr] ]  [ WHILE expr ]   [ FOREVER                                    ]  [ UNTIL expr ]   [ expr                                       ]  ...instructions...  END [symbol]        Repeated execution of a group of instructionsDROP name|(namelist) [name|(namelist) ...]        Unassign named variables and/or list of vars contained in variableEXIT [expression]        Unconditionally leave; optionally return dataIF expression THEN instruction [ELSE instruction]        Conditional executionINTERPRET expression        Execute expression as though it were a line in input fileITERATE [name]        Steps current or named do loopLEAVE [name]        Ends current or named do loopNOP        Dummy instructionNUMERIC DIGITS [expression]        Number of significant digits (default=9; can be arbitrarily high!)NUMERIC FORM SCIENTIFIC|ENGINEERING|VALUE expression        Exponential notation format; default=SCIENTIFICNUMERIC FUZZ expression        Digits, at full precision, to ignore during comparisons (default=0)OPTIONS 'ETMODE'    Check for valid DBCS strings        'NOETMODE'  Don't check for valid DBCS strings (default)        'EXMODE'    Handle DBCS data on a logical character basis        'NOEXMODE'  All string data handled on a byte basis (default)PARSE [UPPER] ARG [template]      Program/subroutine/function parameters              EXTERNAL            Next string from terminal input buffer              LINEIN              Next line from default input stream              NUMERIC             Current DIGITS FUZZ FORM settings              PULL                Next string from program stack              SOURCE              Source of program being executed              VALUE [expr] WITH   Parse result of expression              VAR name            Parse named variable              VERSION             Query REXX version        Assign data to one or more variablesPROCEDURE [EXPOSE name|(namelist) [name|(namelist) ...]]        Protect (localize) variables in internal function or subroutine        By default, all variables are globalPULL [template]        Same as PARSE UPPER PULLPUSH [expression]        Stack resulting string LIFO in program stackQUEUE [expression]        Stack resulting string FIFO in program stackRETURN [expression]        Return control; like EXIT if no internal routine active        Returns result from function; sets RESULT variable from subroutineSAY [expression]        Displays (TYPEs) a line to default output stream (the terminal)SELECT  WHEN expression THEN instruction  WHEN expression THEN instruction  ...etc...  OTHERWISE instruction  END        Case-conditional execution        Only the first matching case is executedSIGNAL label        Pass control to labelSIGNAL [VALUE] expression        Pass control to label evaluated from expressionSIGNAL ON condition [NAME trapname]          ERROR     Host command returns non-zero rc                      (or just positive rc if ON FAILURE too)          FAILURE   Host command returns negative return code          HALT      Attempt to interrupt (such as HI)          NOTREADY  Error during input or output operation          NOVALUE   Uninitialized variable used          SYNTAX    Interpretation syntax error        Signal on specified condition; variable SIGL contains line numberSIGNAL OFF condition        Cancel SIGNAL ON trapTRACE [prefix] [letter]   prefix:      ?=Toggle pause for interactive debug input after trace occurs      !=Toggle inhibit host command execution (try TRACE !C)   letter:      A=All: all clauses traced (displayed) before execution      C=Commands: all host commands traced, non-zero rc's displayed      E=Error: host commands with non-zero rc traced after execution      F=Failure: host commands with negative rc traced after execution      I=Intermediates: All + intermediate results      L=Labels: display labels as passed during execution      N=Normal=Negative: host cmds with negative rc traced after execution      O=Off, or no argument: nothing traced; prefix actions off      R=Results: final (not intermediate) results, plus PULL, ARG, PARSE      S=Scan: trace remaining clauses without executingTRACE [number]   n=skip next n interactive debug pauses  -n=skip next n tracing displaysUPPER variable [variable ...]   Translate contents of named variables to uppercasePARSE SOURCE s.1 s.2 s.3 s.4 s.5 s.6 s.7   s.1 = 'CMS'   s.2 = 'COMMAND'|'FUNCTION'|'SUBROUTINE'   s.3 = Filename   s.4 = Filetype   s.5 = Filemode   s.6 = Name as invoked (possibly different than s.3 if synonym used)   s.7 = Default ADDRESS for commandsTRACE Messages   *-*  Source data in program   +++  Trace message   >>>  Result of expression, parsed value, or returned from subroutine   >.>  Value assigned to placeholder during parsing   during TRACE I:   >C>  Name of compound variable   >F>  Result of function call   >L>  Literal (string or uninitialize variable)   >O>  Result of operation on two terms   >P>  Result of prefix operation   >V>  Contents of a variable