Tokenize a string
You are encouraged to solve this task according to the task description, using any language you may know.
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period.
ActionScript
<lang actionscript>var hello:String = "Hello,How,Are,You,Today"; var tokens:Array = hello.split(","); trace(tokens.join("."));
// Or as a one-liner trace("Hello,How,Are,You,Today".split(",").join("."));</lang>
Ada
<lang ada>with Ada.Strings.Fixed; use Ada.Strings.Fixed; with Ada.Text_Io; use Ada.Text_Io;
procedure Parse_Commas is
Source_String : String := "Hello,How,Are,You,Today"; Index_List : array(1..256) of Natural; Next_Index : Natural := 1;
begin
Index_List(Next_Index) := 1;
while Index_List(Next_Index) < Source_String'Last loop
Next_Index := Next_Index + 1;
Index_List(Next_Index) := 1 + Index(Source_String(Index_List(Next_Index - 1)..Source_String'Last), ",");
if Index_List(Next_Index) = 1 then
Index_List(Next_Index) := Source_String'Last + 2;
end if;
Put(Source_String(Index_List(Next_Index - 1)..Index_List(Next_Index)-2) & ".");
end loop;
end Parse_Commas;</lang>
ALGOL 68
<lang algol68>main:(
OP +:= = (REF FLEX[]STRING in out, STRING item)VOID:( [LWB in out: UPB in out+1]STRING new; new[LWB in out: UPB in out]:=in out; new[UPB new]:=item; in out := new );
PROC string split = (REF STRING beetles, STRING substr)[]STRING:(
""" Split beetles where substr is found """;
FLEX[1:0]STRING out;
INT start := 1, pos;
WHILE string in string(substr, pos, beetles[start:]) DO
out +:= STRING(beetles[start:start+pos-2]);
start +:= pos + UPB substr - 1
OD;
IF start > LWB beetles THEN
out +:= STRING(beetles[start:])
FI;
out
);
PROC char split = (REF STRING beetles, STRING chars)[]STRING: (
""" Split beetles where character is found in chars """;
FLEX[1:0]STRING out;
FILE beetlef;
associate(beetlef, beetles); # associate a FILE handle with a STRING #
make term(beetlef, chars); # make term: assign CSV string terminator #
PROC raise logical file end = (REF FILE f)BOOL: except logical file end; on logical file end(beetlef, raise logical file end);
STRING solo;
DO
getf(beetlef, ($g$, solo));
out+:=solo;
getf(beetlef, ($x$)) # skip CHAR separator #
OD;
except logical file end:
SKIP;
out
);
STRING beetles := "John Lennon, Paul McCartney, George Harrison, Ringo Starr";
printf(($g"."$, string split(beetles, ", "),$l$)); printf(($g"."$, char split(beetles, ", "),$l$))
)</lang>
Output:
John Lennon.Paul McCartney.George Harrison.Ringo Starr. John.Lennon..Paul.McCartney..George.Harrison..Ringo.Starr.
AutoHotkey
<lang AutoHotkey>string := "Hello,How,Are,You,Today" stringsplit, string, string, `, loop, % string0 { msgbox % string%A_Index% }</lang>
AWK
<lang awk>BEGIN {
s = "Hello,How,Are,You,Today"
split(s, arr, ",")
for(i=1; i < length(arr); i++) {
printf arr[i] "."
}
print
}</lang>
A more idiomatic way for AWK is
<lang awk>BEGIN { FS = "," } {
for(i=1; i <= NF; i++) printf $i "."; print ""
}</lang>
which "tokenize" each line of input and this is achieved by using "," as field separator
Batch File
<lang dos>@echo off setlocal enabledelayedexpansion call :tokenize %1 res echo %res% goto :eof
- tokenize
set str=%~1
- loop
for %%i in (%str%) do set %2=!%2!.%%i set %2=!%2:~1! goto :eof</lang>
Demo <lang dos>>tokenize.cmd "Hello,How,Are,You,Today" Hello.How.Are.You.Today</lang>
BASIC
<lang qbasic>DIM parseMe AS STRING parseMe = "Hello,How,Are,You,Today"
DIM tmpLng1 AS INTEGER, tmpLng2 AS INTEGER, parsedCount AS INTEGER tmpLng2 = 1 parsedCount = -1
'count number of tokens DO
tmpLng1 = INSTR(tmpLng2, parseMe, ",")
IF tmpLng1 THEN
parsedCount = parsedCount + 1
tmpLng2 = tmpLng1 + 1
ELSE
IF tmpLng2 < (LEN(parseMe) + 1) THEN parsedCount = parsedCount + 1
EXIT DO
END IF
LOOP
IF parsedCount > -1 THEN
REDIM parsed(parsedCount) AS STRING tmpLng2 = 1 parsedCount = -1
'parse
DO
tmpLng1 = INSTR(tmpLng2, parseMe, ",")
IF tmpLng1 THEN
parsedCount = parsedCount + 1
parsed(parsedCount) = MID$(parseMe, tmpLng2, tmpLng1 - tmpLng2)
tmpLng2 = tmpLng1 + 1
ELSE
IF tmpLng2 < (LEN(parseMe) + 1) THEN
parsedCount = parsedCount + 1
parsed(parsedCount) = MID$(parseMe, tmpLng2)
END IF
EXIT DO
END IF
LOOP
PRINT parsed(0);
FOR L0 = 1 TO parsedCount
PRINT "."; parsed(L0);
NEXT
END IF</lang>
BBC BASIC
<lang bbcbasic> INSTALL @lib$+"STRINGLIB"
text$ = "Hello,How,Are,You,Today"
n% = FN_split(text$, ",", array$())
FOR i% = 0 TO n%-1
PRINT array$(i%) "." ;
NEXT
PRINT</lang>
C
This example uses the strtok() function to separate the tokens. This function is destructive (replacing token separators with '\0'), so we have to make a copy of the string (using strdup()) before tokenizing. strdup() is not part of ANSI C, but is available on most platforms. It can easily be implemented with a combination of strlen(), malloc(), and strcpy().
<lang c>#include<string.h>
- include<stdio.h>
- include<stdlib.h>
int main(void) { char *a[5]; const char *s="Hello,How,Are,You,Today"; int n=0, nn;
char *ds=strdup(s);
a[n]=strtok(ds, ","); while(a[n] && n<4) a[++n]=strtok(NULL, ",");
for(nn=0; nn<=n; ++nn) printf("%s.", a[nn]); putchar('\n');
free(ds);
return 0; }</lang>
C#
<lang csharp>string str = "Hello,How,Are,You,Today"; // or Regex.Split ( "Hello,How,Are,You,Today", "," ); // (Regex is in System.Text.RegularExpressions namespace string[] strings = str.Split(','); foreach (string s in strings) {
Console.WriteLine (s + ".");
}</lang>
C++
This is not the most efficient method as it involves redundant copies in the background, but it is very easy to use. In most cases it will be a good choice as long as it is not used as an inner loop in a performance critical system.
Note doxygen tags in comments before function, describing details of interface.
<lang cpp>#include <string>
- include <vector>
/// \brief convert input string into vector of string tokens /// /// \note consecutive delimiters will be treated as single delimiter /// \note delimiters are _not_ included in return data /// /// \param input string to be parsed /// \param delims list of delimiters.
std::vector<std::string> tokenize_str(const std::string & str,
const std::string & delims=", \t")
{
using namespace std; // Skip delims at beginning, find start of first token string::size_type lastPos = str.find_first_not_of(delims, 0); // Find next delimiter @ end of token string::size_type pos = str.find_first_of(delims, lastPos);
// output vector vector<string> tokens;
while (string::npos != pos || string::npos != lastPos)
{
// Found a token, add it to the vector.
tokens.push_back(str.substr(lastPos, pos - lastPos));
// Skip delims. Note the "not_of". this is beginning of token
lastPos = str.find_first_not_of(delims, pos);
// Find next delimiter at end of token.
pos = str.find_first_of(delims, lastPos);
}
return tokens;
}</lang>
here is sample usage code:
<lang cpp>#include <iostream> int main() {
using namespace std;
string s("Hello,How,Are,You,Today");
vector<string> v(tokenize_str(s));
for (unsigned i = 0; i < v.size(); i++) cout << v[i] << "."; cout << endl; return 0;
}</lang>
Common Lisp
There are libraries out there that handle splitting (e.g., SPLIT-SEQUENCE, and the more-general CL-PPCRE), but this is a simple one-off, too. When the words are written with write-with-periods, there is no final period after the last word.
<lang lisp>(defun comma-split (string)
(loop :for start := 0 :then (1+ finish)
:for finish := (position #\, string :start start)
:collecting (subseq string start finish)
:until (null finish)))
(defun write-with-periods (strings)
(format t "~{~A~^.~}" strings))</lang>
Clojure
<lang lisp>(apply str (interpose "." (seq (.split #"," "Hello,How,Are,You,Today"))))</lang>
D
<lang D>writefln( "Hello,How,Are,You,Today".split(",").join(".") );</lang>
Delphi
<lang Delphi> program TokenizeString;
{$APPTYPE CONSOLE}
uses
Classes;
var
tmp: TStringList; i: Integer;
begin
// Instantiate TStringList class
tmp := TStringList.Create;
try
{ Use the TStringList's CommaText property to get/set
all the strings in a single comma-delimited string }
tmp.CommaText := 'Hello,How,Are,You,Today';
{ Now loop through the TStringList and display each
token on the console }
for i := 0 to Pred(tmp.Count) do
Writeln(tmp[i]);
finally tmp.Free; end;
Readln;
end. </lang>
The result is:
<lang Delphi> Hello How Are You Today </lang>
E
<lang e>".".rjoin("Hello,How,Are,You,Today".split(","))</lang>
Erlang
<lang erlang>-module(tok). -export([start/0]).
start() ->
Lst = string:tokens("Hello,How,Are,You,Today",","),
io:fwrite("~s~n", [string:join(Lst,".")]),
ok.</lang>
Factor
<lang factor>"Hello,How,Are,You,Today" "," split "." join print</lang>
Fantom
A string can be split on a given character, returning a list of the intervening strings.
<lang fantom> class Main {
public static Void main ()
{
str := "Hello,How,Are,You,Today"
words := str.split(',')
words.each |Str word|
{
echo ("${word}. ")
}
}
} </lang>
Forth
There is no standard string split routine, but it is easily written. The results are saved temporarily to the dictionary.
<lang forth>: split ( str len separator len -- tokens count )
here >r 2swap begin 2dup 2, \ save this token ( addr len ) 2over search \ find next separator while dup negate here 2 cells - +! \ adjust last token length 2over nip /string \ start next search past separator repeat 2drop 2drop r> here over - ( tokens length ) dup negate allot \ reclaim dictionary 2 cells / ; \ turn byte length into token count
- .tokens ( tokens count -- )
1 ?do dup 2@ type ." ." cell+ cell+ loop 2@ type ;
s" Hello,How,Are,You,Today" s" ," split .tokens \ Hello.How.Are.You.Today</lang>
Fortran
<lang fortran>PROGRAM Example
CHARACTER(23) :: str = "Hello,How,Are,You,Today" CHARACTER(5) :: word(5) INTEGER :: pos1 = 1, pos2, n = 0, i
DO
pos2 = INDEX(str(pos1:), ",")
IF (pos2 == 0) THEN
n = n + 1
word(n) = str(pos1:)
EXIT
END IF
n = n + 1
word(n) = str(pos1:pos1+pos2-2)
pos1 = pos2+pos1
END DO
DO i = 1, n WRITE(*,"(2A)", ADVANCE="NO") TRIM(word(i)), "." END DO
END PROGRAM Example</lang>
Go
<lang go>package main
import (
"fmt" "strings"
)
func main() {
s := "Hello,How,Are,You,Today" fmt.Println(strings.Join(strings.Split(s, ",", -1), "."))
}</lang>
Haskell
The necessary operations are unfortunately not in the standard library (yet), but simple to write:
<lang haskell>splitBy :: (a -> Bool) -> [a] -> a splitBy _ [] = [] splitBy f list = first : splitBy f (dropWhile f rest) where
(first, rest) = break f list
splitRegex :: Regex -> String -> [String]
joinWith :: [a] -> a -> [a] joinWith d xs = concat $ List.intersperse d xs -- "concat $ intersperse" can be replaced with "intercalate" from the Data.List in GHC 6.8 and later
putStrLn $ joinWith "." $ splitBy (== ',') $ "Hello,How,Are,You,Today"
-- using regular expression to split: import Text.Regex putStrLn $ joinWith "." $ splitRegex (mkRegex ",") $ "Hello,How,Are,You,Today"</lang>
Tokenizing can also be realized by using unfoldr and break: <lang Haskell>*Main> mapM_ putStrLn $ takeWhile (not.null) $ unfoldr (Just . second(drop 1). break (==',')) "Hello,How,Are,You,Today" Hello How Are You Today</lang>
- You need to import the modules Data.List and Control.Arrow
As special cases, splitting / joining by white space and by newlines are provided by the Prelude functions words / unwords and lines / unlines, respectively.
Groovy
<lang groovy>println 'Hello,How,Are,You,Today'.split(',').join('.')</lang>
HicEst
<lang hicest>CHARACTER string="Hello,How,Are,You,Today", list
nWords = INDEX(string, ',', 256) + 1 maxWordLength = LEN(string) - 2*nWords ALLOCATE(list, nWords*maxWordLength)
DO i = 1, nWords
EDIT(Text=string, SePaRators=',', item=i, WordEnd, CoPyto=CHAR(i, maxWordLength, list))
ENDDO
DO i = 1, nWords
WRITE(APPend) TRIM(CHAR(i, maxWordLength, list)), '.'
ENDDO</lang>
Icon and Unicon
<lang icon>procedure main()
A := []
"Hello,How,Are,You,Today" ? while put(A, 1(tab(upto(',')|0),=","))
every writes(!A,".")
write()
end</lang>
Output:
->ss Hello.How.Are.You. ->
Io
<lang io>"Hello,How,Are,You,Today" split(",") join(".") println</lang>
J
<lang j> s=: 'Hello,How,Are,You,Today'
] t=: <;._1 ',',s
+-----+---+---+---+-----+ |Hello|How|Are|You|Today| +-----+---+---+---+-----+
; t,&.>'.'
Hello.How.Are.You.Today.
'.' (I.','=s)}s NB. two steps combined
Hello.How.Are.You.Today</lang>
Alternatively using the system library/script strings <lang j> require 'strings'
',' splitstring s
+-----+---+---+---+-----+ |Hello|How|Are|You|Today| +-----+---+---+---+-----+
'.' joinstring ',' splitstring s
Hello.How.Are.You.Today</lang>
splitstring and joinstring also work with longer "delimiters": <lang j> '"'([ ,~ ,) '","' joinstring ',' splitstring s "Hello","How","Are","You","Today"</lang>
Java
There are multiple ways to tokenize a String in Java. The first is by splitting the String into an array of Strings, and the other way is to use StringTokenizer with a delimiter. The second way given here will skip any empty tokens. So if two commas are given in line, there will be an empty string in the array given by the split function, but no empty string with the StringTokenizer object.
<lang java5>String toTokenize = "Hello,How,Are,You,Today";
//First way String word[] = toTokenize.split(","); for(int i=0; i<word.length; i++) {
System.out.print(word[i] + ".");
}
//Second way StringTokenizer tokenizer = new StringTokenizer(toTokenize, ","); while(tokenizer.hasMoreTokens()) {
System.out.print(tokenizer.nextToken() + ".");
}</lang>
JavaScript
<lang javascript>alert( "Hello,How,Are,You,Today".split(",").join(".") );</lang>
Liberty BASIC
<lang lb>'Note that Liberty Basic's array usage can reach element #10 before having to DIM the array For i = 0 To 4
array$(i) = Word$("Hello,How,Are,You,Today", (i + 1), ",")
array$ = array$ + array$(i) + "."
Next i
Print Left$(array$, (Len(array$) - 1))</lang>
Logo
<lang logo>to split :str :sep
output parse map [ifelse ? = :sep ["| |] [?]] :str
end</lang>
This form is more robust, doing the right thing if there are embedded spaces. <lang logo>to split :str :by [:acc []] [:w "||]
if empty? :str [output lput :w :acc] ifelse equal? first :str :by ~ [output (split butfirst :str :by lput :w :acc)] ~ [output (split butfirst :str :by :acc lput first :str :w)]
end</lang>
<lang logo>? show split "Hello,How,Are,You,Today ", [Hello How Are You Today]</lang>
Lua
<lang lua>require"re"
record = re.compile[[
record <- ( <field> (',' <field>)* ) -> {} (%nl / !.)
field <- <escaped> / <nonescaped>
nonescaped <- { [^,"%nl]* }
escaped <- '"' {~ ([^"] / '""' -> '"')* ~} '"'
]]
print(unpack(record:match"hello,how,are,you,today"))</lang> A different solution using the string-library of Lua: <lang lua>str = "Hello,How,Are,You,Today"
tokens = {} for w in string.gmatch( str, "(%a+)" ) do
tokens[#tokens+1] = w
end
for i = 1, #tokens do
print( tokens[i] )
end</lang>
M4
<lang M4>define(`s',`Hello,How,Are,You,Today') define(`set',`define(`$1[$2]',`$3')') define(`get',`defn($1[$2])') define(`n',0) define(`fill',
`set(a,n,$1)`'define(`n',incr(n))`'ifelse(eval($#>1),1,`fill(shift($@))')')
fill(s) define(`j',0) define(`show',
`ifelse(eval(j<n),1,`get(a,j).`'define(`j',incr(j))`'show')')
show</lang>
Output:
Hello.How.Are.You.Today.
MATLAB
<lang MATLAB>function tokenizeString(string,delimeter)
tokens = {};
while not(isempty(string))
[tokens{end+1},string] = strtok(string,delimeter);
end
for i = (1:numel(tokens)-1)
fprintf([tokens{i} '.'])
end
fprintf([tokens{end} '\n'])
end</lang>
Output: <lang MATLAB>>> tokenizeString('Hello,How,Are,You,Today',',') Hello.How.Are.You.Today</lang>
MAXScript
<lang maxscript>output = "" for word in (filterString "Hello,How,Are,You,Today" ",") do (
output += (word + ".")
) format "%\n" output</lang>
MMIX
<lang mmix>sep IS ',' EOS IS 0 NL IS 10
// main registers p IS $255 tp GREG c GREG t GREG
LOC Data_Segment GREG @ Text BYTE "Hello,How,Are,You,Today",EOS token BYTE 0 eot IS @+255
LOC #100 % main () { Main LDA p,Text % LDA tp,token % initialize pointers 2H LDBU c,p % DO get char BZ c,5F % break if char == EOS CMP t,c,sep % if char != sep then PBNZ t,3F % store char SET t,NL % terminate token with NL,EOS STBU t,tp SET t,EOS INCL tp,1 STBU t,tp JMP 4F % continue
3H STBU c,tp % store char 4H INCL tp,1 % update pointers INCL p,1 JMP 2B % LOOP
5H SET t,NL % terminate last token and buffer STBU t,tp SET t,EOS INCL tp,1 STBU t,tp % next part is not really necessary % program runs only once % INCL tp,1 % terminate buffer % STBU t,tp
LDA tp,token % reset token pointer % REPEAT 2H ADD p,tp,0 % start of token TRAP 0,Fputs,StdOut % output token ADD tp,tp,p INCL tp,1 % step to next token LDBU t,tp PBNZ t,2B % UNTIL EOB(uffer) TRAP 0,Halt,0</lang> Output:
~/MIX/MMIX/Progs> mmix tokenizing Hello How Are You Today
Modula-3
<lang modula3>MODULE Tokenize EXPORTS Main;
IMPORT IO, TextConv;
TYPE Texts = REF ARRAY OF TEXT;
VAR tokens: Texts;
string := "Hello,How,Are,You,Today";
sep := SET OF CHAR {','};
BEGIN
tokens := NEW(Texts, TextConv.ExplodedSize(string, sep));
TextConv.Explode(string, tokens^, sep);
FOR i := FIRST(tokens^) TO LAST(tokens^) DO
IO.Put(tokens[i] & ".");
END;
IO.Put("\n");
END Tokenize.</lang>
MUMPS
<lang MUMPS>TOKENS
NEW I,J,INP SET INP="Hello,how,are,you,today" NEW I FOR I=1:1:$LENGTH(INP,",") SET INP(I)=$PIECE(INP,",",I) NEW J FOR J=1:1:I WRITE INP(J) WRITE:J'=I "." KILL I,J,INP QUIT</lang>
In use:
USER>D TOKENS^ROSETTA Hello.how.are.you.today
Objective-C
<lang objc>NSString *text = @"Hello,How,Are,You,Today"; NSArray *tokens = [text componentsSeparatedByString:@","]; NSString *result = [tokens componentsJoinedByString:@"."]; NSLog(result);</lang>
Objeck
<lang objeck> bundle Default {
class Parse {
function : Main(args : String[]) ~ Nil {
tokens := "Hello,How,Are,You,Today"->Split(",");
each(i : tokens) {
tokens[i]->PrintLine();
};
}
}
} </lang>
OCaml
To split on a single-character separator: <lang ocaml>let rec split_char sep str =
try
let i = String.index str sep in
String.sub str 0 i ::
split_char sep (String.sub str (i+1) (String.length str - i - 1))
with Not_found ->
[str]</lang>
Or the tail-recursive equivalent:
<lang ocaml>(* [try .. with] structures break tail-recursion,
so we externalise it in a sub-function *)
let string_index str c =
try Some(String.index str c) with Not_found -> None
let split_char sep str =
let rec aux acc str =
match string_index str sep with
| Some i ->
let this = String.sub str 0 i
and next = String.sub str (i+1) (String.length str - i - 1) in
aux (this::acc) next
| None ->
List.rev(str::acc)
in
aux [] str
- </lang>
But both of these will process extraneous String.sub (so one string alloc). For N tokens there will be (N - 2) unneeded allocs. To resolve this here is a version which first gets the indices, and then extracts the tokens:
<lang ocaml>let split_char sep str =
let rec indices acc i =
try
let i = succ(String.index_from str i sep) in
indices (i::acc) i
with Not_found ->
(String.length str + 1) :: acc
in
let is = indices [0] 0 in
let rec aux acc = function
| last::start::tl ->
let w = String.sub str start (last-start-1) in
aux (w::acc) (start::tl)
| _ -> acc
in
aux [] is</lang>
Splitting on a string separator using the regular expressions library: <lang ocaml>#load "str.cma";; let split_str sep str =
Str.split (Str.regexp_string sep) str</lang>
There is already a library function for joining: <lang ocaml>String.concat sep strings</lang>
Oz
<lang oz>for T in {String.tokens "Hello,How,Are,You,Today" &,} do
{System.printInfo T#"."}
end</lang>
Perl
<lang perl>print join('.', split /,/, 'Hello,How,Are,You,Today'), "\n";</lang>
Perl 6
<lang perl6>'Hello,How,Are,You,Today'.split(',').join('.').say;</lang>
PicoLisp
<lang PicoLisp>(mapcar pack
(split (chop "Hello,How,Are,You,Today") ",") )</lang>
PHP
<lang php><?php $str = 'Hello,How,Are,You,Today'; echo implode('.', explode(',', $str)); ?></lang>
PL/I
<lang PL/I> declare s character (100) initial ('Hello,How,Are,You,Today'); declare n fixed binary (31);
n = tally(s, ',')+1;
begin;
declare table(n) character (50) varying; declare c character (1); declare (i, k) fixed binary (31);
table = ; k = 1;
do i = 1 to length(s);
c = substr(s, i, 1);
if c = ',' then k = k + 1;
else table(k) = table(k) || c;
end;
/* display the table */ table = table || '.'; put skip list (string(table));
end; </lang>
Pop11
The natural solution in Pop11 uses lists.
There are built in libraries for tokenising strings, illustrated below, along with code that the user could create for the task.
First show the use of sysparse_string to break up a string and make a list of strings.
<lang pop11>;;; Make a list of strings from a string using space as separator lvars list; sysparse_string('the cat sat on the mat') -> list;
- print the list of strings
list =>
- [the cat sat on the mat]</lang>
By giving it an extra parameter 'true' we can make it recognize numbers and produce a list of strings and numbers
<lang pop11>lvars list; sysparse_string('one 1 two 2 three 3 four 4', true) -> list;
- print the list of strings and numbers
list =>
- [one 1 two 2 three 3 four 4]
- check that first item is a string and second an integer
isstring(list(1))=>
- <true>
isinteger(list(2))=>
- <true></lang>
Now show some uses of the built in procedure sys_parse_string, which allows more options:
<lang pop11>;;; Make pop-11 print strings with quotes true -> pop_pr_quotes;
- Create a string of tokens using comma as token separator
lvars str='Hello,How,Are,You,Today';
- Make a list of strings by applying sys_parse_string
- to str, using the character `,` as separator (the default
- separator, if none is provided, is the space character).
lvars strings; [% sys_parse_string(str, `,`) %] -> strings;
- print the list of strings
strings =>
- ['Hello' 'How' 'Are' 'You' 'Today']</lang>
If {% ... %} were used instead of [% ... %] the result would be a vector (i.e. array) of strings rather than a list of strings.
<lang pop11>{% sys_parse_string(str, `,`) %} -> strings;
- print the vector
strings =>
- {'Hello' 'How' 'Are' 'You' 'Today'}</lang>
It is also possible to give sys_parse_string a 'conversion' procedure, which is applied to each of the tokens. E.g. it could be used to produce a vector of numbers, using the conversion procedure 'strnumber', which converts a string to a number:
<lang pop11>lvars numbers; {% sys_parse_string('100 101 102 103 99.9 99.999', strnumber) %} -> numbers;
- the result is a vector containing integers and floats,
- which can be printed thus
numbers =>
- {100 101 102 103 99.9 99.999}</lang>
Using lower level pop-11 facilities to tokenise the string:
<lang pop11>;;; Declare and initialize variables lvars str='Hello,How,Are,You,Today';
- Iterate over string
lvars ls = [], i, j = 1; for i from 1 to length(str) do
;;; If comma
if str(i) = `,` then
;;; Prepend word (substring) to list
cons(substring(j, i - j, str), ls) -> ls;
i + 1 -> j;
endif;
endfor;
- Prepend final word (if needed)
if j <= length(str) then
cons(substring(j, length(str) - j + 1, str), ls) -> ls;
endif;
- Reverse the list
rev(ls) -> ls;</lang>
Since the task requires to use array we convert list to array
<lang pop11>;;; Put list elements and lenght on the stack destlist(ls);
- Build a vector from them
lvars ar = consvector();
- Display in a loop, putting trailing period
for i from 1 to length(ar) do
printf(ar(i), '%s.');
endfor; printf('\n');</lang>
We could use list directly for printing:
<lang pop11>for i in ls do
printf(i, '%s.');
endfor;</lang>
so the conversion to vector is purely to satisfy task formulation.
PowerBASIC
PowerBASIC has a few keywords that make parsing strings trivial: PARSE, PARSE$, and PARSECOUNT. (PARSE$, not shown here, is for extracting tokens one at a time, while PARSE extracts all tokens at once into an array. PARSECOUNT returns the number of tokens found.)
<lang powerbasic>FUNCTION PBMAIN () AS LONG
DIM parseMe AS STRING parseMe = "Hello,How,Are,You,Today"
REDIM parsed(PARSECOUNT(parseMe) - 1) AS STRING PARSE parseMe, parsed() 'comma is default delimiter
DIM L0 AS LONG, outP AS STRING
outP = parsed(0)
FOR L0 = 1 TO UBOUND(parsed) 'could reuse parsecount instead of ubound
outP = outP & "." & parsed(L0)
NEXT
MSGBOX outP
END FUNCTION</lang>
PowerShell
<lang powershell>$words = "Hello,How,Are,You,Today".Split(',') [string]::Join('.', $words)</lang>
<lang powershell>$words = "Hello,How,Are,You,Today" -split ',' $words -join '.'</lang>
Prolog
<lang prolog>splitup(Sep,[token(B)|BL]) --> splitup(Sep,B,BL). splitup(Sep,[A|AL],B) --> [A], {\+ [A] = Sep }, splitup(Sep,AL,B). splitup(Sep,[],[B|BL]) --> Sep, splitup(Sep,B,BL). splitup(_Sep,[],[]) --> []. start :-
phrase(splitup(",",Tokens),"Hello,How,Are,You,Today"),
phrase(splitup(".",Tokens),Backtogether),
string_to_list(ABack,Backtogether),
writeln(ABack).</lang>
Output:
?- start. Hello.How.Are.You.Today
PureBasic
As described <lang PureBasic>NewList MyStrings.s()
For i=1 To 5
AddElement(MyStrings())
MyStrings()=StringField("Hello,How,Are,You,Today",i,",")
Next i
ForEach MyStrings()
Print(MyStrings()+".")
Next</lang>
Still, easier would be <lang PureBasic>Print(ReplaceString("Hello,How,Are,You,Today",",","."))</lang>
Python
<lang python>text = "Hello,How,Are,You,Today" tokens = text.split(',') print ('.'.join(tokens))</lang>
Or if interpretation of the task description means you don't need to keep an intermediate array: <lang python>print ('.'.join('Hello,How,Are,You,Today'.split(',')))</lang>
R
<lang R>text <- "Hello,How,Are,You,Today" junk <- strsplit(text, split=",") print(paste(unlist(junk), collapse="."))</lang>
or the one liner
<lang R>paste(unlist(strsplit(text, split=",")), collapse=".")</lang>
Raven
<lang raven>'Hello,How,Are,You,Today' ',' split '.' join print</lang>
REBOL
<lang REBOL>print ["Original:" original: "Hello,How,Are,You,Today"] tokens: parse original "," dotted: "" repeat i tokens [append dotted rejoin [i "."]] print ["Dotted: " dotted]</lang>
Output:
Original: Hello,How,Are,You,Today Dotted: Hello.How.Are.You.Today.
Retro
<lang Retro>{{
: char ( -$ ) " " ; : tokenize ( $-$$ ) @char ^strings'splitAtChar withLength 1- over + 0 swap ! tempString ; : action ( $- ) keepString ^buffer'add ;
---reveal---
: split ( $cb- ) ^buffer'set !char char ^strings'append [ tokenize action dup 1 <> ] while drop ^buffer'get drop ;
}}</lang>
This will suffice to split a string into an array of substrings. It is used like this:
<lang Retro>create strings 100 allot "Hello,How,Are,You,Today" ', strings split</lang>
Since the buffer' vocabulary creates a zero-terminated buffer, we can display it using the each@ combinator and a simple quote:
<lang Retro>strings [ @ "%s." puts ] ^types'STRING each@</lang>
REXX
version 1
<lang rexx>sss='Hello,How,Are,You,Today' /*words seperated by commas. */ say 'input string='sss /*echo the string to console. */ say new=sss /*make a copy of the string. */
do items=1 until new== /*keep going until SSS is empty.*/ parse var new a.items ',' new /*parse words delinated by comma*/ end
say 'Words in the string:' /*Display a header for the list.*/
do k=1 for items /*Now, display all the words. */
say a.k'.' /*append a period to the word. */
end
say 'End-of-list.' /*Display a trailer for the list*/</lang> Output:
input string=Hello,How,Are,You,Today Words in the string: Hello. How. Are. You. Today. End-of-list.
version 2
<lang rexx>sss='Hello,How,Are,You,Today' /*words seperated by commas. */ say 'input string='sss /*echo the string to console. */ say say 'Words in the string:' /*Display a header for the list. */
do until sss== /*keep going until SSS is empty. */ parse var sss x ',' sss /*parse words delinated by comma.*/ say x'.' /*show a word appended with a '.'*/ end
say 'End-of-list.' /*Display a trailer for the list.*/</lang> Output is identical to Version 1.
Ruby
<lang ruby>puts "Hello,How,Are,You,Today".split(',').join('.')</lang>
Scala
<lang scala>println("Hello,How,Are,You,Today" split "," mkString ".")</lang>
Scheme
<lang scheme>(use-modules (ice-9 regex)) (define s "Hello,How,Are,You,Today") (define words (map match:substring (list-matches "[^,]+" s)))
(do ((n 0 (+ n 1))) ((= n (length words)))
(display (list-ref words n))
(if (< n (- (length words) 1))
(display ".")))</lang>
Seed7
<lang seed7>var array string: tokens is 0 times "";
tokens := split("Hello,How,Are,You,Today", ",");</lang>
Slate
<lang slate>('Hello,How,Are,You,Today' splitWith: $,) join &separator: '.'.</lang>
Smalltalk
<lang smalltalk>|array | array := 'Hello,How,Are,You,Today' subStrings: $,. array fold: [:concatenation :string | concatenation, '.', string ]</lang>
Some implementations also have a join: convenience method that allows the following shorter solution:
<lang smalltalk>('Hello,How,Are,You,Today' subStrings: $,) join: '.'</lang>
The solution displaying a trailing period would be:
<lang smalltalk>|array | array := 'Hello,How,Are,You,Today' subStrings: $,. array inject: into: [:concatenation :string | concatenation, string, '.' ]</lang>
SNOBOL4
For this task, it's convenient to define Perl-style split( ) and join( ) functions.
<lang SNOBOL4> define('split(chs,str)i,j,t,w2') :(split_end) split t = table() sp1 str pos(0) (break(chs) | rem) $ t + span(chs) (break(chs) | ) . w2 = w2 :s(sp1)
- t = differ(str,) str ;* Uncomment for CSnobol
split = array(i)
sp2 split<j = j + 1> = t<j> :s(sp2)f(return) split_end
define('join(ch,a)i,') :(join_end)
join join = join a
join = join ?a ch :s(join)f(return)
join_end
- # Test and display
output = join('.',split(',','Hello,How,Are,You,Today'))
end</lang>
Output:
Hello.How.Are.You.Today
Standard ML
<lang sml>val splitter = String.tokens (fn c => c = #","); val main = (String.concatWith ".") o splitter;</lang>
Test:
<lang sml>- main "Hello,How,Are,You,Today" val it = "Hello.How.Are.You.Today" : string</lang>
Tcl
Generating a list form a string by splitting on a comma: <lang tcl>split $string ","</lang>
Joining the elements of a list by a period: <lang tcl>join $list "."</lang>
Thus the whole thing would look like this: <lang tcl>puts [join [split "Hello,How,Are,You,Today" ","] "."]</lang>
If you'd like to retain the list in a variable with the name "words", it would only be marginally more complex: <lang tcl>puts [join [set words [split "Hello,How,Are,You,Today" ","]] "."]</lang>
(In general, the regexp command is also used in Tcl for tokenization of strings, but this example does not need that level of complexity.)
tr
<lang tr>echo 'Hello,How,Are,You,Today' | tr ',' '.'</lang>
TUSCRIPT
<lang tuscript> $$ MODE TUSCRIPT SET string="Hello,How,Are,You,Today" SET string=SPLIT (string,":,:") SET string=JOIN (string,".") </lang>
UnixPipes
<lang bash>rtoken() {
(IFS=\ read A B ; echo $A; test -n "$B" && (echo $B | token) )
}
tokens() {
IFS=, read A ; echo $A | rtoken
}
echo "Hello,How,Are,You" | tokens</lang>
Ursala
A list of strings is made by separating at the commas using the library function, sep. A single string is then made by joining the list of strings with periods using the library function, mat. Each of these is a second order function parameterized by the delimiter. Character literals are preceded by a backquote. <lang Ursala>#import std
token_list = sep`, 'Hello,How,Are,You,Today'
- cast %s
main = mat`. token_list</lang> output:
'Hello.How.Are.You.Today'
VBScript
One liner
<lang vb>wscript.echo Join( Split( "Hello,How,Are,You,Today", "," ), "." )</lang>
In fact, the following Visual Basic could have done the same, as Join() is available.
Visual Basic
Unlike PowerBASIC, there is no need to know beforehand how many tokens are in the string -- Split automagically builds the array for you.
<lang vb>Sub Main()
Dim parseMe As String, parsed As Variant parseMe = "Hello,How,Are,You,Today"
parsed = Split(parseMe, ",")
Dim L0 As Long, outP As String
outP = parsed(0)
For L0 = 1 To UBound(parsed)
outP = outP & "." & parsed(L0)
Next
MsgBox outP
End Sub</lang>
Vedit macro language
Vedit does not use the concepts of array or list. Normally, the text is processed as text in an edit buffer.
However, this example shows how to split the text into multiple text registers (10, 11, 12 etc.). The contents of each text register is then displayed to user, separated by a period.
<lang vedit>Buf_Switch(Buf_Free) Ins_Text("Hello,How,Are,You,Today")
// Split the text into text registers 10, 11, ... BOF
- 1 = 9
Repeat(ALL) {
#1++
#2 = Cur_Pos
Search(",", ADVANCE+ERRBREAK)
Reg_Copy_Block(#1, #2, Cur_Pos-1)
} Reg_Copy_Block(#1, #2, EOB_Pos)
// Display the list for (#3 = 10; #3 <= #1; #3++) {
Reg_Type(#3) Message(".")
}
Buf_Quit(OK)</lang>
Zsh
<lang zsh>str='Hello,How,Are,You,Today' tokens=(${(s:,:)str}) print ${(j:.:)tokens}</lang>
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