DragonFly On-Line Manual Pages

Search: Section:  

SNOBOL4EXT(1)                   CSNOBOL4 Manual                  SNOBOL4EXT(1)


NAME

       snobol4ext - CSNOBOL4 extensions


DESCRIPTION

       This page describes extensions to the Bell Telephone Laboratories
       portable implementation of SNOBOL4 in snobol4(1).

       ARRAY/TABLE access
           Multiple ARRAY and/or TABLE index operations may appear in a row,
           without having to resort to use of the ELEMENT function, so long as
           no intervening spaces (or line continuations) appear.

       Case folding
           By default the compiler folds identifiers and directives to upper
           case, so programs can be entered in either case: see snobol4(1),
           -CASE in snobol4ctrl(1), &CASE in snobol4key(1).

       Control lines
           The following additional ``control lines'' are implemented: -CASE,
           -COPY, -ERROR, -NOERRORS, -EXECUTE, -NOEXECUTE, -HIDE, -INCLUDE,
           -LINE: See snobol4ctrl(1).

       Functions
           The following additional functions are implemented: ATAN(),
           BREAKX(), CHAR(), CHOP() COS(), DATE(), DELETE(), EXP(), FILE(),
           FILE_ABSPATH(), FILE_ISDIR() FREEZE(), FUNCTION(), HOST(),
           IO_FINDUNIT() LABEL(), LEQ(), LGE(), LLE(), LLT(), LN(), LNE(),
           LOG(), LPAD(), ORD(), RENAME(), REVERSE(), RPAD(), RSORT(), SET()
           SETEXIT(), SIN(), SORT(), SQRT(), SSET(), SUBSTR(), TAN(), THAW(),
           VDIFFER(): see snobol4func(1).

       Keywords
           The following additional keywords are implemented: &CASE, &DIGITS,
           &ERRTEXT &FILE, &GCTIME, >RACE &LASTFILE, &LASTLINE, &LCASE,
           &LINE, &MAXINT, &PARM, &PI, &STEXEC, &UCASE: see snobol4key(1).

       REAL numbers in INTEGER contexts
           REAL numbers (or strings convertible to REAL) are accepted in all
           contexts which previously required an INTEGER (or string
           convertible to INTEGER).  Contexts include TABLE(), ITEM(), array
           indices, INPUT(), OUTPUT(), SET(), keyword values, CHAR(), RPAD(),
           LPAD(), FIELD(), COLLECT(), DUMP(), DUPL(), OPSYN(), SUBSTR().

       Scientific notation
           REAL number syntax has been expanded to allow exponents of the
           form: ANY('Ee') ('+' | '-' | '') SPAN('0123456789').  Exponential
           format reals need not contain a decimal point.

       SPITBOL operators
           The SPITBOL scan (?) and assignment (=) operators have been added.
           A pattern match can appear within an expression, and returns the
           matched string as its value.  Similarly assignment can appear in an
           expression, and returns the assigned value. An assignment after a
           scan (ie; STRING ? PATTERN = VALUE) performs a scan and replace.
           Assignment is right associative, and has the lowest precedence,
           while scan is left associative and has a precedence just higher
           than assignment.

           The SPITBOL selection/alternative construction can be used in any
           expression.  It consists of a comma separated list of expressions
           inside parentheses.  The expressions are evaluated until one
           succeeds, and its value is returned.  Abuse of this construction
           may result in incomprehensible code.

           The type NUMERIC with CONVERT() and the removal of leading spaces
           from strings converted to numbers (implicitly or explicitly) are
           also legal when SPITBOL extensions are enabled.  SPITBOL extensions
           can be enabled and disabled using the -PLUSOPS directive.  -PLUSOPS
           0 or -PLUSOPS disables SPITBOL operators, while -PLUSOPS n where n
           is a non-zero integer enables them.  SPITBOL extensions are enabled
           by default.

       TERMINAL I/O variable
           The variable TERMINAL is associated with the standard error file
           descriptor for both input and output.

       TRACE() function type argument
           The second argument of the TRACE() function can be abbreviated to a
           single letter: C (CALL), F (FUNCTION), K (KEYWORD), L (LABEL), R
           (RETURN), or V (VALUE) as in Macro SPITBOL.

       TRACE() of additional keywords
           &ERRTEXT and &STFCOUNT can be traced.

       Value TRACE() on pattern match assignments
           variable changes by . and $ operators are visible via value trace.


BUGS

       A lot of stuff still needs to move to other pages!

       Group the keywords, control lines, functions, operators together!


SEE ALSO

       snobol4(1).  snobol4ctrl(1), snobol4func(1), snobol4key(1).

CSNOBOL4B 2.0                   January 1, 2015                  SNOBOL4EXT(1)

Search: Section: