
Parse::RPN - Is a minimalist RPN parser/processor (a little like FORTH) $Revision: 47 $

use Parse::RPN; $result=rpn(string ...); @results=rpn(string ...); $error=rpn_error(); string... is a list of RPN operator and value separated by a coma in scalar mode RPN return the result of the calculation (If the stack contain more then one element, you receive a warning and the top value on the stack) in array mode, you receive the content of the stack after evaluation

rpn() receive in entry a scalar of one or more elements coma separated and evaluate as an RPN (Reverse Polish Notation) command. The function split all elements and put in the stack. The operator are case sensitive. The operator are detect as is, if they are alone in the element of the stack. Extra space before or after are allowed (e.g "3,4,ADD" here ADD is an opeartor but it is not the case in "3,4,ADD 1") If element is not part of the predefined operator (dictionary), the element is push as a litteral. If you would like to put a string which is part of the dictionary, put it between quote or double-quote (e.g "3,4,'ADD'" here ADD is a literal and the evaluation reurn ADD and a warning because the stack is not empty) If the string contain a coma, you need also to quote or double-quote the string. (be care to close your quoted or double-quoted string) The evaluation follow the rule of RPN or FORTH or POSTCRIPT or pockect calcutor HP. Look on web for documentation about the use of RPN notation. I use this module in a application where the final user need to create an maintain a configuration file with the possibility to do calculation on variable returned from application. The idea of this module is comming from Math::RPN of Owen DeLong, owen@delong.com that I used for more then a year before some of my customer would like more ... I correct a bug (interversion of > and >=), add the STRING function, pattern search and some STACK functions. rpn_error() return the last error from the evaluation (illegal division by 0, error from the PERL function execution...) each time that rpn() is call the rpn_error() is reinitianised.

.
return the result of 'a' + 'b'
return the result of 'a' - 'b'
return the result of 'a' * 'b'
return the result of 'a' / 'b'
if b =0 return '' (to prevent exception raise)
return the result of 'a' ** 'b' (exponant)
return the result of 'a' +1
return the result of 'a' -1
return the result of 'a' -2
return the result of 'a' +2
return the result of 'a' % 'b'
return the result of abs 'a'
return the result of INT 'a'
return the result negate value of 'a' (- 'a' )
return the result of 'a' - int 'a' (fractional part of 'a' )
return the result of sin 'a' ('a' in RADIAN)
return the result of cos 'a' ('a' in RADIAN)
return the result of tan 'a' ('a' in RADIAN)
return the result of cotan 'a' ('a' in RADIAN)
return the result of ln 'a'
if = 0 return '' (to prevent exception raise)
return the result of 'e' ** 'a'
return the value of PI (3.14159265358979)

.
return the result of 'a' < 'b' ( BOOLEAN value )
return the result of 'a' <= 'b' ( BOOLEAN value )
return the result of 'a' > 'b' ( BOOLEAN value )
return the result of 'a' >= 'b' ( BOOLEAN value )
return the result of 'a' == 'b' ( BOOLEAN value ) 1 if a == b else 0
return the result of 'a' <=> 'b' ( BOOLEAN value ) -1 if a < b ,0 if a == b, 1 if a > b
return the result of 'a' != 'b' ( BOOLEAN value ) 0 if a == b else 1
return the result of 'a' || 'b' ( BOOLEAN value ) 0 if a == b else 1

return the 1 one of the 2 argument are not equal to 0
return the 0 one of the 2 argument are equal to 0
return the 0 if the 2 argument are equal
return the 0 if the argument is not eqauk to 0
return the 1 if the argument is eqauk to 0
return the 1 if the top of stack is !=0 and if stack not empty
return the 0 if the top of stack is !=0

bitwise shift to the right
shift the bits in a to the left of b level
bitwise shift to the left
shift the bits in a to the left of b level
return the result smallest of the 2 arguments
return the result greatest of the 2 arguments
test with the "operator" the [a] value on each elements of VAL and if test succeed return the value from array RET with the same index
the "operator" must be quoted to prevent evaluation
test with the perl "operator" the [a] value on each elements of VAL and if test succeed return the value from array RET with the same index
the "operator" must be quoted to prevent evaluation
loop on each item of array VAL and test the value [ a ] with the operator from ope ARRAY against the corresponding value in array VAL and return the value from array RET with the same index
loop on each item of array VAL and test the value [ a ] with the perl operator from ope ARRAY against the corresponding value in array VAL and return the value from array RET with the same index
return the current time in ticks
return the localtime coresponding to the ticks value 'a'
the format is 'sec' 'min' 'hour' 'day_in_the_month' 'month' 'year' 'day_in_week' 'day_year' 'dayloight_saving'
'year' is the elapsed year since 1900
'month' start to 0
The format is the same as localtime() in perl
return the gmtime coresponding to the ticks value 'a'
the format is 'sec' 'min' 'hour' 'day_in_the_month' 'month' 'year' 'day_in_week' 'day_year' 'dayloight_saving'
'year' is the elapsed year since 1900
'month' start to 0
The format is the same as gmtime() in perl
return the localtime coresponding to the ticks value 'a' in a human readable format
return the gmtime coresponding to the ticks value 'a' in a human readable format
return a random value in the range [0,1[
return a random value in the range [0,'a'[
return the number 'a' formated with space each 3 digits
return the number 'a' formated with . (dot) each 3 digits
return the number 'a' normalize by slice of 1000 with extra power value "K", "M", "G", "T", "P" (or nothing if lower than 1000)
return the number 'a' normalize by slice of 1024 with extra power value "K", "M", "G", "T", "P" (or nothing if lower than 1024)
return the decimal value for the HEX, BINARY or OCTAL value 'a'
OCTAL is like '0nn' where n is in the range of 0-7
BINARY is like '0bnnn...' where n is in the range of 0-1
HEX is like '0xnnn' where n is in the range of 0-9A-F
if no specific format convert as an hexadecimal by default
return a HEX string from a OCTETSTRING.
useful when receiving an SNMP ASN.1 OCTETSTRING like mac address
return a OCTETSTRING string from a HEX
useful when you need to check if an SNMP ASN.1 OCTETSTRING if matching the hex value provided
return a string from a dotted DEC string
useful when you need to manipulate an SNMP extension with 'exec'
return a dotted DEC string to a string
useful when you need to manipulate an SNMP extension with 'exec'

.
return the result of 'a' EQ 'b' ( BOOLEAN value )
return the result of 'a' NE 'b' ( BOOLEAN value )
return the result of 'a' LT 'b' ( BOOLEAN value )
return the result of 'a' GT 'b' ( BOOLEAN value )
return the result of 'a' LE 'b' ( BOOLEAN value )
return the result of 'a' GE 'b' ( BOOLEAN value )
return the result of 'a' CMP 'b' ( BOOLEAN value )
return the length of 'a' EQ 'b'
return the concatenation 'a' and 'b'
return the concatenation all element on the stack
return the result of 'a' x 'b' duplicate 'a' by the number of 'x'
return the reverse of 'a' EQ 'b'
return the substring of 'c' starting at 'b' with the length of 'a'
return 'a' in uppercase
return 'a' in lowercase
return 'a' with the first letter in uppercase
return 'a' with the first letter in lowercase
return all splitted item of 'a' by the separator 'b'
'b' is a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
!!! if the split match on the beginning of string,
SPLIT return the matched value WITHOUT the empty string of the beginning
return all splitted item of 'a' by the separator 'b'
'b' is a REGEX case insensitive
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
!!! if the split match on the beginning of string,
SPLIT return the matched value WITHOUT the empty string of the beginning
return one or more occurance of 'b' in 'a'
'b' is a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
return one or more occurance of 'b' in 'a'
'b' is a REGEX case insensitive
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
test if the pattern 'b' is in 'a'
'b' is a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
test if the pattern 'b' is in 'a'
'b' is a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
substitute the pattern 'b' by the pattern 'a' in 'c'
'b' and 'c' are a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
substitute the pattern 'b' by the pattern 'a' in 'c' as many time as possible (g flag in REGEX)
'b' and 'c' are a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
substitute the pattern 'b' by the pattern 'a' in 'c'case insensitive (i flag in REGEX)
'b' and 'c' are a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
substitute the pattern 'b' by the pattern 'a' in 'c' as many time as possible (g flag in REGEX)
and case insensitive (1 flag in REGEX)
'b' and 'c' are a REGEX
!!! becare, if you need to use : as a regex, you need to backslash to prevent overlap with new dictionary entry
use the format 'z' to print the value(s) on the stack
7,3,/,10,3,/,%d %f,PRINTF -> 2 3.333333
see printf in perl
pack the value 'a' with the format 'b'
2004,06,08,a4 a2 a2,PACK -> 20040608
see pack in perl
unpack the value 'a' with the format 'b'
20040608,a4 a2 a2,PACK -> 2004,06,08
see unpack in perl
test if top of the stack is a number
return 1 if if it is a NUMBER otherwise return 0
test if top of the stack is a number
delete the top element on the statck and return 1 if it is a NUMBER otherwise return 0
test if top of the stack is a integer (natural number)
return 1 if if it is a INTEGER otherwise return 0
test if top of the stack is a integer (natural number)
delete the top element on the statck and return 1 if it is a INTEGER otherwise return 0
test if top of the stack is a hexadecimal value (starting with 0x or 0X or # )
return 1 if if it is a HEXADECIMAL otherwise return 0
test if top of the stack is a hexadecimal value (starting with 0x or 0X or # )
delete the top element on the statck and return 1 if it is a HEXADECIMAL otherwise return 0

.
return 'b' 'a'
return 'a' 'b' 'a'
return 'a' 'a'
return 'a' 'b' 'a' 'b'
return 'b' 'c' 'a'
return 'c' 'a' 'b'
return the number of elements on the stack
remove the last element on the stack
remove the 'z' last element(s) from the stack
rotate the stack on 'n' element
a,b,c,d,e,4,ROLL -> a c d e b
if n = 3 <=> ROT
copy element from depth 'a' to the stack
get (remove) element from depth 'a'
and put on top of stack
put element 'a' at the level 'b' of the stack
if 'b' gretaer than the stack put at first place
if 'b' < 0 start to the reverse order of the stack
delete 'b' element on the stack from level 'a'
'a' and 'b' is get in absolute value
get the level of stack containing the exact value 'a'
get the first level of stack containing the REGEX 'a'
get the first level of stack containing the REGEX 'a' (cas insensitive)
keep all level of stack containing the REGEX 'a' (cas sensitive)
keep all level of stack containing the REGEX 'a' (cas insensitive)
delete all element on the stack except the level 'a'
if 'a' is deeper then stack, keep the stack untouched
keep 'b' element on the stack from level 'a'
and delete all other element
'a' and 'b' is get in absolute value
keep element on the stack from level 'a'
to level 'b'
and delete all other element
'a' and 'b' is get in absolute value
if 'a' > 'b' keep the reverse of selection (boustrophedon)
copy element on the stack from level 'a'
to level 'b'
'a' and 'b' is get in absolute value
if 'a' > 'b' keep the reverse of selection (boustrophedon)
sum the a element on top of the stack
remove these a element
and return the result value on the stack
STATS the a element on top of the stack
remove these a element
the new variable _SUM_, _MULT_, _ARITH_MEAN_, _GEOM_MEAN_, _QUAD_MEAN_ (= _RMS_), _HARM_MEAN_, _STD_DEV_, _SAMPLE_STD_DEV_, _VARIANCE_,

.
return as one stack element the list of WORD in DICT separated by a |
return as one stack element the list of VARS separated by a |
incremente (+ 1) the value of the variable on the statck
decremente (- 1) the value of the variable on the statck
deckare the variable 'xxx' (reserve memory)
set the value xx to the variable 'var'
put and delete 'n' element(s) from the stack in the variable 'var'
'n' is in absolute value
copy 'n' element(s) from the stack in the variable 'var'
'n' is in absolute value
put and delete ' element(s) from the stack in the variable 'var'
starting at element 'a' to element 'b'
'a' and 'b' in absolute value
if 'a' > 'b' keep the reverse of selection (boustrophedon)
copy element(s) on the stack in the variable 'var'
starting at element 'a' to element 'b'
'a' and 'b' in absolute value
if 'a' > 'b' keep the reverse of selection (boustrophedon)
return the value of the variable 'var'
create a new entry in the dictionary whith name name1 and store the progam xxx
execute the PERL code
with parameter(s) xxx yyy
!!! be care if the perl code need to use a coma (,)
you need to enclose the line inside double quote
if you need double quote in code use qq{ ... }
execute the PERL function name1 with the parameter xxx
the default name space is "main::"
It is possible tu use a specific name space
the paramter are "stringified"
e.g. ':,5,filename,save,PERLFUNC'
call the function save("filename", 5);
put 'a' on the return stack
remove first element from the return stack and copy on the normal stack
return the depth of the return stack
copy return stack on normal stack

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test the element on top of stack
if == 1 execute 'xxx' block
The loop is executed always one time
test the element on top of stack
if == 1 execute 'xxx' block
if != 1 execute 'zzz' block
The loop is executed always one time
execute 'xxx' block
test the element on top of stack
if == 0 execute 'zzz' block and branch again at 'BEGIN'
if != 0 end the loop
The loop is executed always one time
process 'block' with iterator from value 'start' until 'end' value,with increment of 1;
The iterator variable is the second value on the stack (start argument)
process 'block' with iterator from value 'start' untill 'end' value,with increment of 'increment'
This allow rational or negative value
The iterator variable is the second value on the stack (start argument)

. =head2 rpn_error()
function which return the debug info from the calculation (like a division by 0)
function to set a specific separator for the returned stack (default = space)
This is useful when the result of rpn() is use inside another rpn() call

The operators get value from the stack and push the result on top
In the following explanation, the stack is represented as a pair of brackets ()
and each elements by a pair of square barcket []
The left part is the state before evalutation
and the right part is the state of the stack after evaluation
Arithmetic operators
---------------------
+ ([a][b]) ([a+b])
- ([a][b]) ([a-b])
* ([a][b]) ([a*b])
/ ([a][b]) ([a/b]) Becare if division by null return a blank value
** ([a][b]) ([a**b])
1+ ([a]) ([a+1])
1- ([a]) ([a-1])
2+ ([a]) ([a+2])
2- ([a]) ([a-2])
MOD ([a][b]) ([a%b])
ABS ([a]) ([ABS a])
INT ([a]) ([INT a])
+- ([a]) ([-a])
REMAIN ([a]) ([a- INT a])
Rationnal operators
-------------------
SIN ([a]) ([SIN a]) Unit in radian
COS ([a]) ([COS a]) Unit in radian
TAN ([a]) ([TAN a]) Unit in radian
CTAN ([a]) ([CTAN a]) Unit in radian
LN ([a]) ([LOG a])
EXP ([a]) ([EXP a])
PI ([3.14159265358979])
Relational operator
----------------
< ([a][b]) ([1]) if [a]<[b] else ([0])
<= ([a][b]) ([1]) if [a]<=[b] else ([0])
> ([a][b]) ([1]) if [a]>[b] else ([0])
>= ([a][b]) ([1]) if [a]>=[b] else ([0])
== ([a][b]) ([1]) if [a]==[b] else ([0])
<=> ([a][b]) ([-1]) if [a]>[b],([1]) if [a]<[b], ([0])if [a]==[b]
!= ([a][b]) ([0]) if [a]==[b] else ([1])
TRUE ([a]) Return 1 if [a]>0 and exist
FALSE ([a]) Return 0 if [a]>0
Logical operator
----------------
OR ([a][b]) ([1]) if [a] or [b] >0
AND ([a][b]) ([1]) if [a] and [b] >0
XOR ([a][b]) ([1]) if [a] and [b] are >0 or ==0
NOT ([a]) Return 0 if [a]>0, Return 1 if[a]==0,
Other operator
----------------
>> ([a][b]) shift to the right the bits from [a] of [b] rank
<< ([a][b]) shift to the left the bits from [a] of [b] rank
MIN ([a][b]) ([a]) if [a]<[b] else ([b])
MAX ([a][b]) ([a]) if [a]>[b] else ([b])
LOOKUP ([a] V R [ope] ) test [ a ] on all value of array V with the operator [ope]
if succeed, return the value from array R at the succesfull indice
LOOKUPP ([a] V R [ope] ) test [ a ] on all value of array V with the perl operator [ope]
if succeed, return the value from array R at the succesfull indice
LOOKUPOP ([a] V R O] ) test [ a ] on all value of array V with the operator from the array OPE with the same indice
LOOKUPOPP ([a] V R O] ) test [ a ] on all value of array V with the perl operator from the array OPE with the same indice
if succeed, return the value from array R at the succesfull indice
TICK () ([time]) time in ticks
LTIME ([a]) ([min][hour][day_in_the_month][month][year][day_in_week][day_year][daylight_saving]
localtime of [a] like PERL
GTIME ([a]) ([min][hour][day_in_the_month][month][year][day_in_week][day_year][daylight_saving]
([a]) gmtime of [a] like PERL
HLTIME ([a]) ([a]) localtime human readeable
HGTIME ([a]) gmtime human readeable
RAND () ([rand]) a random numder between 0 and 1
LRAND ([a]) ([rand]) a random numder between 0 and [a]
SPACE ([a]) Return [a] with space between each 3 digits
DOT ([a]) Return [a] with dot (.) between each 3 digits
NORM ([a]) Return [a] normalized by 1000 (K,M,G = 1000 * unit)
NORM2 ([a]) Return [a] normalized by 1000 (K,M,G = 1024 * unit)
OCT (|a|) Return the DECIMAL value from HEX,OCTAL or BINARY value |a| (see oct from perl)
OCTSTR2HEX (|a|) Return a HEX string from a OCTETSTRING
OCTSTR2HEX (|a|) Return a OCTETSTRING string from a HEX
DDEC2STR (|a|) Return a string from a dotted DEC string
STR2DDEC (|a|) Return a dotted DEC string to a string
String operators
----------------
EQ ([a][b]) ([1]) if [a] eq [b] else ([0])
NE ([a][b]) ([1]) if [a] ne [b] else ([0])
LT ([a][b]) ([1]) if [a] lt [b] else ([0])
GT ([a][b]) ([1]) if [a] gt [b] else ([0])
LE ([a][b]) ([1]) if [a] le [b] else ([0])
GE ([a][b]) ([1]) if [a] ge [b] else ([0])
CMP ([a][b]) ([-1]) if [a] gt [b],([1]) if [a] lt [b], ([0])if [a] eq [b]
LEN ([a]) ([LENGTH a])
CAT ([a][b]) ([ab]) String concatenation
CATALL ([a][b]...[z]) ([ab...z]) String concatenation of all elements on the stack
REP ([a][b]) ([a x b]) repeat [b] time the motif [a]
REV ([a]) ([REVERSE a])
SUBSTR ([a][b][c]) ([SUBSTR [a], [b], [c]) get substring of [a] starting from [b] untill [c]
UC ([a]) ([UC a])
LC ([a]) ([LC a])
UCFIRST ([a]) ([UCFIRST a])
LCFIRST ([a]) ([LCFIRST a])
PAT ([a][b]) ([r1]...) use the pattern [b] on the string [a] and return result
if more then one result like $1, $2 ... return all the results
PATI ([a][b]) ([r1]...) use the pattern CASE INSENSITIVE [b] on the string [a] and return result
if more then one result like $1, $2 ... return all the results
TPAT ([a][b]) ([r]) use the pattern [b] on the string [a] and return 1 if pattern macth
otherwise return 0
TPATI ([a][b]) ([r]) use the pattern CASE INSENSITIVE [b] on the string [a] and return 1 if pattern macth
otherwise return 0
SPLIT ([a][b]) split ([a]) using the pattern ([b]) and return all elements on stack
SPLITI split ([a]) using the pattern CASE INSENSITIVE ([b])) and return all elements on stack
SPAT ([a][b][c]) Do a pattern subsititution following this rule I<[c] =~s/[a]/[b]/>
SPATG ([a][b][c]) Do a pattern subsititution following this rule I<[c] =~s/[a]/[b]/g>
SPATI ([a][b][c]) Do a pattern subsititution following this rule I<[c] =~s/[a]/[b]/i>
(case insensitive)
SPATGI ([a][b][c]) Do a pattern subsititution following this rule I<[c] =~s/[a]/[b]/gi>
(case insensitive)
PRINTF ([a][b]...[x]) use the format present in [a] to print the value [b] to [x]
the format is the same as (s)printf
PACK ([a][b]...[x]) Do an unpack on variable [b] to [x] using format [b]
UNPACK ([a][b]) Do an unpack on variable [b] using format [a]
ISNUM ([a]) Test if a is a NUMBER return 1 if success ( [a] [1|0] )
Keep the value on the stack
ISNUMD ([a]) Test if a is a NUMBER return 1 if success ( [1|0] )
Remove the value from the stack
ISINT ([a]) Test if a is a INTEGER (natural number )
Return 1 if success ( [a] [1|0] )
Keep the value on the stack
ISINTD ([a]) Test if a is a INTEGER (natural number )
Return 1 if success ( [1|0] )
Remove the value from the stack
ISHEX ([a]) Test if a is a HEXADECIMAL (hex starting with 0x or 0X or # )
Return 1 if success ( [a] [1|0] )
Keep the value on the stack
ISHEXD ([a]) Test if a is a HEXADECIMAL (hex starting with 0x or 0X or # )
Return 1 if success ( [1|0] )
Remove the value from the stack
Stack operators
---------------
SWAP ([a][b]) ([b][a])
OVER ([a][b]) ([a][b][a])
DUP ([a]) ([a][a])
DDUP ([a][b]) ([a][b][a][b])
ROT ([a][b][c]) ([b][c][a])
RROT ([a][b][c]) ([c][a][b])
DEPTH ([r1]...) ([re1]...[nbr]) Return the number of elements in the statck
POP ([a][b]) ([a])
POPN ([a][b][c]...[x]) ([l]...[x]) remove [b] element from the stack (starting at [c])
SWAP2 ([a][b][c]) ([a][c][b])
ROLL ([a][b][c][d][e][n]) ([a][c][d][e][b]) rotate the [n] element of the stack (here [n]=4)
if [n] =3 it is equivalent to ROT
PICK ([a][b][c][d][e][n]) ([a][b][c][d][e][b]) copy element from depth [n] on top
GET ([a][b][c][d][e][n]) ([a][b][c][d][e][b]) get element from depth [n] and put on top
PUT ([a][b][c][d][v][n]) ([a][v][b][c][d]) put element [v] at level [n] (here [n]=3)
DEL ([a][b]) delete [b] element on the stack from level [a]
[a] and [b] is get in absolute value
KEEPN ([a][b]) keep [b] element(s) on the stack from level [a]
(and delete all other elements)
[a] and [b] is get in absolute value
PRESERVE ([a][b]) keep element(s) on the stack from level [a] to level [b]
(and delete all other elements)
[a] and [b] is get in absolute value
COPY ([a][b]) copy element(s) on the stack from level [a] to level [b]
[a] and [b] is get in absolute value
FIND ([a]) get the level of stack containing [a]
SEARCH ([a]) get the level of stack containing the REGEX [a]
SEARCHI ([a]) get the level of stack containing the REGEX [a] ( case insensitive )
SEARCHK ([a]) keep only level of stack matching the REGEX [a]
SEARCHIK ([a]) keep only level of stack matching the REGEX [a] ( case insensitive )
KEEP ([a][b][c][d][e][n]) remove all elements of the stack except the element at deepth |n|
Dictionary operators
--------------------
WORDS () ([a])return as one stack element the list of WORD in DICT separated by a |
VARS () ([a])return as one stack element the list of VARIABLE in VAR separated by a |
INC ([a]) () increment (+1) the value of variable [a]
DEC ([a]) () decrement (-1) the value of variable [a]
VARIABLE ([a]) () create a entry in VAR for the variable [a]
! ([a][b]) store the value [a] in the variable [b]
!! ([a][b][c]...[n] [var]) put and delete 'n' element(s) from the stack in the variable 'var'
'n' is in absolute value
!!C ([a][b][c]...[n] [var]) copy 'n' element(s) from the stack in the variable 'var'
'n' is in absolute value
!!! ([a][b][c]...[n1] [n2] [var]) put and delete element(s) from the stack in the variable 'var'
starting at element 'a' to element 'b'
'a' and 'b' in absolute value
if 'a' > 'b' keep the reverse of selection (boustrophedon)
!!!C ([a][b][c]...[n] [var]) copy 'element(s) from the stack in the variable 'var'
starting at element 'a' to element 'b'
'a' and 'b' in absolute value
if 'a' > 'b' keep the reverse of selection (boustrophedon)
@ ([a]) ([a]) return the value of the variable [a]
: xxx yyy ; create a new word (sub) into the dictionary with the xxx "code" and name yyy
: xxx yyy PERLFUNC execute the PERL function yyy with parameter(s) yyy
the default name space is "main::"
It is possible tu use a specific name space
: xxx yyy PERL execute the PERL code xxx ; yyy
Return Stack operators
----------------------
>R ([a]) put ^a$ on the return stack
R> () remove first element from the return stack and copy on the normal
RL () return the depth of the return stack
R@ () copy return stack ion normal stack
LOOP and DECISION operators
---------------------------
[a] IF [..xxx] THEN Test the element on top of stack
if ==0, execute 'xxx' block
The loop is executed always one time
[a] IF [...zzz...] ELSE [..xxx...] THEN Test the element on top of stack
if ==0, execute 'xxx' block
if != 0 execute 'zzz' block
The loop is executed always one time
BEGIN xxx WHILE zzz REPEAT Execute 'xxx' block
Test the element on top of stack
if ==0 execute 'zzz' block and branch again to BEGIN
if != 0 end the loop
The loop is executed always one time
[a] [b] DO [...xxx...] LOOP ([a][b]) process block [...xxx...] with iterator from value [b] untill [a] value,
with increment of 1;
The iterator variable is '_I_' (read only and scoop only the DO ... LOOP block)
[a] [b] DO [...xxx...] [c] +LOOP ([a][b]) process block [...xxx...] with iterator from value [b] untill [a] value,
with increment of [c];
The iterator variable is '_I_' (read only and scoop only the DO ... LOOP block)

use Parse::RPN;
$test ="3,5,+";
$ret = rpn($test); # $ret = 8
$test = "Hello World,len,3,+";
$ret = rpn($test); # $ret = 14
$test = "'Hello,World',len,3,+";
$ret = rpn($test); # $ret = 14
$test = "'Hello,World,len,3,+";
---------^-----------^-
$ret = rpn($test); # $ret = 8 with a warning because the stack is not empty ([Hello] [8])
# be care to close your quoted string
$test = "'Hello world','or',PAT,'or',EQ,IF,'string contain or',ELSE,'No or in string',THEN"
$ret = rpn($test); # $ret = "Contain a coma"
$test = "'Hello world','or',TPAT,IF,'string contain or',ELSE,'No or in string',THEN";
$ret = rpn($test); # $ret = "string contain or"
$test = "3,10,/,5,+,82,*,%b,PRINTF";
$ret = rpn($test); # $ret = "110110010"
$test = "3,10,/,5,+,82,*,%016b,PRINTF";
$ret = rpn($test); # $ret = "0000000110110010"
$test = "55,N,pack,B32,unpack,^0+(?=\d), ,spat,'+',ds";
$ret = rpn($test); # $ret = 110111
$test = "7,3,/,10,3,/,%d %f,PRINTF";
@ret = rpn($test); # @ret = 2 3.333333
$test = "VARIABLE,a,0,a,!,##,b,BEGIN,bbbb,a,INC,a,@,4,<,WHILE,####,a,@,****,REPEAT";
@ret =rpn($test); # @ret = ## b bbbb #### 1 **** bbbb #### 2 **** bbbb #### 3 **** bbbb
$test = "VARIABLE,a,0,a,!,z,0,5,-1,DO,a,INC,6,1,2,DO,A,_I_,+LOOP,#,+LOOP,##,a,@";
@ret =rpn($test); # @ret = z A 3 A 5 A 7 # A 3 A 5 A 7 # A 3 A 5 A 7 # A 3 A 5 A 7 # A 3 A 5 A 7 # A 3 A 5 A 7 # ## 6
$test = "1,2,3,4,5,6,7,8,9,3,KEEP";
ret =rpn($test); # @ret = 7
$test = "1,2,3,4,5,6,7,8,9,30,KEEP";
ret =rpn($test); # @ret = 1,2,3,4,5,6,7,8,9
$test = "h,g,f,e,d,c,b,a,4,3,DEL";
ret =rpn($test); # @ret = h,c,b,a
$test = "h,g,f,e,d,c,b,a,4,3,KEEPN"";
ret =rpn($test); # @ret = g,f,e,d
sub Test {
my $a = shift;
my $b = shift;
my $c = $a/$b;
print "a=$a\tb=$b\ttotal=$c\n";
return $c;
}
$test = ":,5,6,Test,PERLFUNC";
@ret =rpn($test); # call the function "Test" from the main package (the caller) with parameter 5,6 and return result (in @ret)
$test = ":,05,11,01,0,0,0,Time::Local::timelocal,PERLFUNC";
@ret =rpn($test); # @ret = 1133391600
$test = "1,2,3,+,:, my $b=7, "open LOG , qq{ >/tmp/log }",print LOG time,PERL";
@ret =rpn($test); # @ret = 1,5
and the file /tmp/log contain a line with the tick time.
$test = "11,55,*,5,2,401,+,:,my $b=,SWAP,CAT, "open LOG , qq{ >/tmp/log }",print LOG $b.qq{ \n },PERL"
@ret =rpn($test); # @ret =1 2 3 1 (the latest 1 is the succes result return)
and the file /tmp/log contain a line with 403 + a cariage return
$test = 'mb,tb,gb,mb,kb,4,V,!!,12,9,6,3,4,R,!!,V,R,"TPATI",LOOKUP'
@ret =rpn($test); # @ret = 6
$test = '5,1,2,3,4,5,5,V,!!," "," ",ok," ",nok,5,R,!!,V,R,"<=",LOOKUPP'
@ret =rpn($test); # @ret = nok
$test = '3,1,2,3,4,5,5,V,!!,a,b,ok,d,nok,5,R,!!,"<","<","<","<","<",5,O,!!,V,R,O,LOOKUPOPP'
@ret =rpn($test); # @ret = d
The small tool 'RPN.pl' provide an easy interface to test quickly an RPN.
This include two test functions named 'save' and 'restore'
Try RPN.pl to get a minimal help.
Take a look to the minimalistic code, and put RPN.pl in your path.
Sample of use:
RPN.pl -r '1,2,3,:,123,100,+,7,*,test,save,PERLFUNC'
save in file '/tmp/test' the value '1561' (whithout CR/LF) and return 1 2 3 1

Fabrice Dulaunoy <fabrice@dulaunoy.com>
It is a full rewrite from the version 1.xx to allow DICTIONNARY use
and STRUCTURE control
Thanks to the module Math::RPN from Owen DeLong, <owen@delong.com>
for the idea of using RPN in a config file

Math-RPN from Owen DeLong, <owen@delong.com>

Error processing, stack underflow...

Thank's to Stefan Moser <sm@open.ch> for the idea
to call a perl function from the rpn() and also for pin-pointing an error in stack return.

Under the GNU GPL2
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public
License as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the
Free Software Foundation, Inc., 59 Temple Place,
Suite 330, Boston, MA 02111-1307 USA
Parse::RPN Copyright (C) 2004 2005 2006 2007 DULAUNOY Fabrice
Parse::RPN comes with ABSOLUTELY NO WARRANTY;
for details See: L<http://www.gnu.org/licenses/gpl.html>
This is free software, and you are welcome to redistribute
it under certain conditions;