Replace % in the end of string with Regex? - regex

I want to remove " %" at the end of some text. I'd like to do it with a regular expression, because ABAP does not easily handle text at the end of a string.
DATA lv_vtext TYPE c LENGTH 10 VALUE 'TEST %'.
REPLACE REGEX ' %$' IN lv_vtext WITH ''.
But it does not replace anything. When I leave out "$" the text will be removed as expected, but I fear it might find more occurrences than wanted.
I experimented with \z or \Z instead of $, but to no avail.

This answer is about an alternative way without REGEX. POSIX regular expressions are quite slow, moreover some people are reluctant to use it, so if you're not completely closed to do it in normal ABAP:
lv_vtext = COND #( WHEN contains( val = lv_vtext end = ` %` )
THEN substring( val = lv_vtext len = strlen( lv_vtext ) - 2 )
ELSE lv_vtext ).
Code with context:
DATA(lv_vtext) = `test %`.
lv_vtext = COND #( WHEN contains( val = lv_vtext end = ` %` )
THEN substring( val = lv_vtext len = strlen( lv_vtext ) - 2 )
ELSE lv_vtext ).
ASSERT lv_vtext = `test`.

You can use
REPLACE REGEX '\s%\s*$' IN lv_vtext WITH ''
The benefit of using \s is that it matches any Unicode whitespace chars. The \s*$ matches any trailing (white)spaces that you might have missed.
The whole pattern matches
\s - any whitespace
% - a % char
\s* - zero or more whitespaces
$ - at the end of string.

Related

Kotlin .split() with multiple regex

Input: """aaaabb\\\\\cc"""
Pattern: ["""aaa""", """\\""", """\"""]
Output: [aaa, abb, \\, \\, \, cc]
How can I split Input to Output using patterns in Pattern in Kotlin?
I found that Regex("(?<=cha)|(?=cha)") helps patterns to remain after spliting, so I tried to use looping, but some of the patterns like '\' and '[' require escape backslash, so I'm not able to use loop for spliting.
EDIT:
val temp = mutableListOf<String>()
for (e in Input.split(Regex("(?<=\\)|(?=\\)"))) temp.add(e)
This is what I've been doing, but this does not work for multiple regex, and this add extra "" at the end of temp if Input ends with "\"
You may use the function I wrote for some previous question that splits by a pattern keeping all matched and non-matched substrings:
private fun splitKeepDelims(s: String, rx: Regex, keep_empty: Boolean = true) : MutableList<String> {
var res = mutableListOf<String>() // Declare the mutable list var
var start = 0 // Define var for substring start pos
rx.findAll(s).forEach { // Looking for matches
val substr_before = s.substring(start, it.range.first()) // // Substring before match start
if (substr_before.length > 0 || keep_empty) {
res.add(substr_before) // Adding substring before match start
}
res.add(it.value) // Adding match
start = it.range.last()+1 // Updating start pos of next substring before match
}
if ( start != s.length ) res.add(s.substring(start)) // Adding text after last match if any
return res
}
You just need a dynamic pattern from yoyur Pattern list items by joining them with a |, an alternation operator while remembering to escape all the items:
val Pattern = listOf("aaa", """\\""", "\\") // Define the list of literal patterns
val rx = Pattern.map{Regex.escape(it)}.joinToString("|").toRegex() // Build a pattern, \Qaaa\E|\Q\\\E|\Q\\E
val text = """aaaabb\\\\\cc"""
println(splitKeepDelims(text, rx, false))
// => [aaa, abb, \\, \\, \, cc]
See the Kotlin demo
Note that between \Q and \E, all chars in the pattern are considered literal chars, not special regex metacharacters.

Split with a multicharacter regex pattern and keep delimiters

I have next string and regex for splitting it:
val str = "this is #[loc] sparta"
val regex = "((?<=( #\\[\\w{3,100}\\] ))|(?=( #\\[\\w{3,100}\\] )))"
print(str.split(Regex(regex)))
//print - [this is, #[loc] , sparta]
Works fine. But in develop I did not realize when in #[***] block must be a not only text (\w) - he have and "-" and numbers (UUID), and my correct blocks is -
val str = "this is #[loc_75acca83-a39b-4df1-8c3c-b690df00db62]"
and in this case regex don't work.
How to change this part - "\w{3,100}" for new requirements?
I try change to any - "\.{3,100}" - not work
To fix your issue, you may replace your regex with
val regex = """((?<=( #\[[^\]\[]{3,100}] ))|(?=( #\[[^\]\[]{3,100}] )))"""
The \w can be replaced with [^\]\[] that matches any char but [ and ].
Note the use of a raw string literal, """...""", that allows the use of a single backslash as a regex escape.
See the Kotlin online demo.
Alternatively, you may use the following method to split and keep delimiters:
private fun splitKeepDelims(s: String, rx: Regex, keep_empty: Boolean = true) : MutableList<String> {
var res = mutableListOf<String>() // Declare the mutable list var
var start = 0 // Define var for substring start pos
rx.findAll(s).forEach { // Looking for matches
val substr_before = s.substring(start, it.range.first()) // // Substring before match start
if (substr_before.length > 0 || keep_empty) {
res.add(substr_before) // Adding substring before match start
}
res.add(it.value) // Adding match
start = it.range.last()+1 // Updating start pos of next substring before match
}
if ( start != s.length ) res.add(s.substring(start)) // Adding text after last match if any
return res
}
Then, just use it like
val str = "this is #[loc_75acca83-a39b-4df1-8c3c-b690df00db62] sparta"
val regex = """#\[[\]\[]+]""".toRegex()
print(splitKeepDelims(str, regex))
// => [this is , #[loc_75acca83-a39b-4df1-8c3c-b690df00db62], sparta]
See the Kotlin demo.
The \[[^\]\[]+] pattern matches
\[ - a [ char
[^\]\[]+ - 1+ chars other than [ and ]
] - a ] char.

Stripping comments from Forth source code using regular expressions

I am trying to match all content between parentheses, including parentheses in a non-greedy way. There should be a space before and after the opening parentheses (or the start of a line before the opening parentheses) and a space before and after the closing parentheses. Take the following text:
( )
( This is a comment )
1 2 +
\ a
: square dup * ;
( foo bar
baz )
(quux)
( ( )
(
( )
The first line should be matched, the second line including its content should be matched, the second last line should not be matched (or raise an error) and the last line should be matched. The two lines foo bar baz should be matched, but (quux) should not as it doesn't contain a space before and after the parentheses. The line with the extra opening parentheses inside should be matched.
I tried a few conventional regexes for matching content between parentheses but without much success. The regex engine is that of Go's.
re := regexp.MustCompile(`(?s)\(( | .*? )\)`)
s = re.ReplaceAllString(s, "")
Playground: https://play.golang.org/p/t93tc_hWAG
Regular expressions "can't count" (that's over-simplified, but bear with me), so you can't match on an unbounded amount of parenthesis nesting. I guess you're mostly concerned about matching only a single level in this case, so you would need to use something like:
foo := regexp.MustCompile(`^ *\( ([^ ]| [^)]*? \)$`)
This does require the comment to be the very last thing on a line, so it may be better to add "match zero or more spaces" there. This does NOT match the string "( ( ) )" or try to cater for arbitrary nesting, as that's well outside the counting that regular expressions can do.
What they can do in terms of counting is "count a specific number of times", they can't "count how many blah, then make sure there's the same number of floobs" (that requires going from a regular expression to a context-free grammar).
Playground
Here is a way to match all the 3 lines in question:
(?m)^[\t\p{Zs}]*\([\pZs}\t](?:[^()\n]*[\pZs}\t])?\)[\pZs}\t]*$
See the Go regex demo at the new regex101.com
Details:
(?m) - multiline mode on
^ - due to the above, the start of a line
[\t\p{Zs}]* - 0+ horizontal whitespaces
\( - a (
[\pZs}\t] - exactly 1 horizontal whitespace
(?:[^()\n]*[\pZs}\t])? - an optional sequence matching:
[^()\n]* - a negated character class matching 0+ characters other than (, ) and a newline
[\pZs}\t] - horizontal whitespace
\) - a literal )
[\pZs}\t]* - 0+ horizontal whitespaces
$ - due to (?m), the end of a line.
Go playground demo:
package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)^[\t\p{Zs}]*\([\pZs}\t](?:[^()\n]*[\pZs}\t])?\)[\pZs}\t]*$`)
var str = ` ( )
( This is a comment )
1 2 +
\ a
: square dup * ;
( foo bar
baz )
(quux)
( ( )
(
( )`
for i, match := range re.FindAllString(str, -1) {
fmt.Println("'", match, "' (found at index", i, ")")
}
}

Regex - Quantifier {x,y} following nothing

I'm creating a basic text editor and I'm using regex to achieve a find and replace function. To do this I've gotten this code:
Private Function GetRegExpression() As Regex
Dim result As Regex
Dim regExString As [String]
' Get what the user entered
If TabControl1.SelectedIndex = 0 Then
regExString = txtbx_Find2.Text
ElseIf TabControl1.SelectedIndex = 1 Then
regExString = txtbx_Find.Text
End If
If chkMatchCase.Checked Then
result = New Regex(regExString)
Else
result = New Regex(regExString, RegexOptions.IgnoreCase)
End If
Return result
End Function
And this is the Find method
Private Sub FindText()
''
Dim WpfTest1 As New Spellpad.Tb
Dim ElementHost1 As System.Windows.Forms.Integration.ElementHost = frm_Menu.Controls("ElementHost1")
Dim TheTextBox As System.Windows.Controls.TextBox = CType(ElementHost1.Child, Tb).ctrl_TextBox
''
' Is this the first time find is called?
' Then make instances of RegEx and Match
If isFirstFind Then
regex = GetRegExpression()
match = regex.Match(TheTextBox.Text)
isFirstFind = False
Else
' match.NextMatch() is also ok, except in Replace
' In replace as text is changing, it is necessary to
' find again
'match = match.NextMatch();
match = regex.Match(TheTextBox.Text, match.Index + 1)
End If
' found a match?
If match.Success Then
' then select it
Dim row As Integer = TheTextBox.GetLineIndexFromCharacterIndex(TheTextBox.CaretIndex)
MoveCaretToLine(TheTextBox, row + 1)
TheTextBox.SelectionStart = match.Index
TheTextBox.SelectionLength = match.Length
Else
If TabControl1.SelectedIndex = 0 Then
MessageBox.Show([String].Format("Cannot find ""{0}"" ", txtbx_Find2.Text), Application.ProductName, MessageBoxButtons.OK, MessageBoxIcon.Information)
ElseIf TabControl1.SelectedIndex = 1 Then
MessageBox.Show([String].Format("Cannot find ""{0}"" ", txtbx_Find.Text), Application.ProductName, MessageBoxButtons.OK, MessageBoxIcon.Information)
End If
isFirstFind = True
End If
End Sub
When I run the program I get errors:
For ?, parsing "?" - Quantifier {x,y} following nothing.; and
For *, parsing "*" - Quantifier {x,y} following nothing.
It's as if I can't use these but I really need to. How can I solve this problem?
? and * are quantifiers in regular expressions:
? is used to specify that something is optional, for instance b?au can match both bau and au.
* means the group with which it binds can be repeated zero, one or multiple times: for instance ba*u can bath bu, bau, baau, baaaaaaaau,...
Now most regular expressions use {l,u} as a third pattern with l the lower bound on the number of times something is repeated, and u the upper bound on the number of occurences. So ? is replaced by {0,1} and * by {0,}.
Now if you provide them without any character before them, evidently, the regex parser doesn't know what you mean. In other words if you do (used csharp, but the ideas are generally applicable):
$ csharp
Mono C# Shell, type "help;" for help
Enter statements below.
csharp> Regex r = new Regex("fo*bar");
csharp> r.Replace("Fooobar fooobar fbar fobar","<MATCH>");
"Fooobar <MATCH> <MATCH> <MATCH>"
csharp> r.Replace("fooobar far qux fooobar quux fbar echo fobar","<MATCH>");
"<MATCH> far qux <MATCH> quux <MATCH> echo <MATCH>"
If you wish to do a "raw text find and replace", you should use string.Replace.
EDIT:
Another way to process them is by escaping special regex characters. Ironically enough, you can do this by replacing them by a regex ;).
Private Function GetRegExpression() As Regex
Dim result As Regex
Dim regExString As [String]
' Get what the user entered
If TabControl1.SelectedIndex = 0 Then
regExString = txtbx_Find2.Text
ElseIf TabControl1.SelectedIndex = 1 Then
regExString = txtbx_Find.Text
End If
'Added code
Dim baseRegex As Regex = new Regex("[\\.$^{\[(|)*+?]")
regExString = baseRegex.Replace(regExString,"\$0")
'End added code
If chkMatchCase.Checked Then
result = New Regex(regExString)
Else
result = New Regex(regExString, RegexOptions.IgnoreCase)
End If
Return result
End Function

PCRE regex for multiple decimal coordinates using [lon,lat] format

I am trying to create a regex for [lon,lat] coordinates.
The code first checks if the input starts with '['.
If it does we check the validity of the coordinates via a regex
/([\[][-+]?(180(\.0{1,15})?|((1[0-7]\d)|([1-9]?\d))(\.\d{1,15})?),[-+]?([1-8]?\d(\.\d{1,15})?|90(\.0{1,15})?)[\]][\;]?)+/gm
The regex tests for [lon,lat] with 15 decimals [+- 180degrees, +-90degrees]
it should match :
single coordinates :
[120,80];
[120,80]
multiple coordinates
[180,90];[180,67];
[180,90];[180,67]
with newlines
[123,34];[-32,21];
[12,-67]
it should not match:
semicolon separator missing - single
[25,67][76,23];
semicolon separator missing - multiple
[25,67]
[76,23][12,90];
I currently have problems with the ; between coordinates (see 4 & 5)
jsfiddle equivalent here : http://regex101.com/r/vQ4fE0/4
You can try with this (human readable) pattern:
$pattern = <<<'EOD'
~
(?(DEFINE)
(?<lon> [+-]?
(?:
180 (?:\.0{1,15})?
|
(?: 1(?:[0-7][0-9]?)? | [2-9][0-9]? | 0 )
(?:\.[0-9]{1,15})?
)
)
(?<lat> [+-]?
(?:
90 (?:\.0{1,15})?
|
(?: [1-8][0-9]? | 9)
(?:\.[0-9]{1,15})?
)
)
)
\A
\[ \g<lon> , \g<lat> ] (?: ; \n? \[ \g<lon> , \g<lat> ] )* ;?
\z
~x
EOD;
explanations:
When you have to deal with a long pattern inside which you have to repeat several time the same subpatterns, you can use several features to make it more readable.
The most well know is to use the free-spacing mode (the x modifier) that allows to indent has you want the pattern (all spaces are ignored) and eventually to add comments.
The second consists to define subpatterns in a definition section (?(DEFINE)...) in which you can define named subpatterns to be used later in the main pattern.
Since I don't want to repeat the large subpatterns that describes the longitude number and the latitude number, I have created in the definition section two named pattern "lon" and "lat". To use them in the main pattern, I only need to write \g<lon> and \g<lat>.
javascript version:
var lon_sp = '(?:[+-]?(?:180(?:\\.0{1,15})?|(?:1(?:[0-7][0-9]?)?|[2-9][0-9]?|0)(?:\\.[0-9]{1,15})?))';
var lat_sp = '(?:[+-]?(?:90(?:\\.0{1,15})?|(?:[1-8][0-9]?|9)(?:\\.[0-9]{1,15})?))';
var coo_sp = '\\[' + lon_sp + ',' + lat_sp + '\\]';
var regex = new RegExp('^' + coo_sp + '(?:;\\n?' + coo_sp + ')*;?$');
var coordinates = new Array('[120,80];',
'[120,80]',
'[180,90];[180,67];',
'[123,34];[-32,21];\n[12,-67]',
'[25,67][76,23];',
'[25,67]\n[76,23]');
for (var i = 0; i<coordinates.length; i++) {
console.log("\ntest "+(i+1)+": " + regex.test(coordinates[i]));
}
fiddle
Try this out:
^(\[([+-]?(?!(180\.|18[1-9]|19\d{1}))\d{1,3}(\.\d{1,15})?,[+-]?(?!(90\.|9[1-9]))\d{1,2}(\.\d{1,15})?(\];$|\]$|\];\[)){1,})
Demo: http://regex101.com/r/vQ4fE0/7
Explanation
^(\[
Must start with a bracket
[+-]?
May or may not contain +- in front of the number
(?!(180\.|18[1-9]|19\d{1}))
Should not contain 180., 181-189 nor 19x
\d{1,3}(\.\d{1,15})?
Otherwise, any number containing 1 or 3 digits, with or without decimals (up to 15) are allowed
(?!(90\.|9[1-9]))
The 90 check is similar put here we are not allowing 90. nor 91-99
\d{1,2}(\.\d{1,15})?
Otherwise, any number containing 1 or 2 digits, with or without decimals (up to 15) are allowed
(\];$|\]$|\];\[)
The ending of a bracket body must have a ; separating two bracket bodies, otherwise it must be the end of the line.
{1,}
The brackets can exist 1 or multiple times
Hope this was helpful.
This might work. Note that you have a lot of capture groups, none of which
will give you good information because of recursive quantifiers.
# /^(\[[-+]?(180(\.0{1,15})?|((1[0-7]\d)|([1-9]?\d))(\.\d{1,15})?),[-+]?([1-8]?\d(\.\d{1,15})?|90(\.0{1,15})?)\](?:;\n?|$))+$/
^
( # (1 start)
\[
[-+]?
( # (2 start)
180
( \. 0{1,15} )? # (3)
|
( # (4 start)
( 1 [0-7] \d ) # (5)
|
( [1-9]? \d ) # (6)
) # (4 end)
( \. \d{1,15} )? # (7)
) # (2 end)
,
[-+]?
( # (8 start)
[1-8]? \d
( \. \d{1,15} )? # (9)
|
90
( \. 0{1,15} )? # (10)
) # (8 end)
\]
(?: ; \n? | $ )
)+ # (1 end)
$
Try a function approach, where the function can do some of the splitting for you, as well as delegating the number comparisons away from the regex. I tested it here: http://repl.it/YyG/3
//represents regex necessary to capture one coordinate, which
// looks like 123 or 123.13532
// the decimal part is a non-capture group ?:
var oneCoord = '(-?\\d+(?:\\.\\d+)?)';
//console.log("oneCoord is: "+oneCoord+"\n");
//one coordinate pair is represented by [x,x]
// check start/end with ^, $
var coordPair = '^\\['+oneCoord+','+oneCoord+'\\]$';
//console.log("coordPair is: "+coordPair+"\n");
//the full regex string consists of one or more coordinate pairs,
// but we'll do the splitting in the function
var myRegex = new RegExp(coordPair);
//console.log("my regex is: "+myRegex+"\n");
function isPlusMinus180(x)
{
return -180.0<=x && x<=180.0;
}
function isPlusMinus90(y)
{
return -90.0<=y && y<=90.0;
}
function isValid(s)
{
//if there's a trailing semicolon, remove it
if(s.slice(-1)==';')
{
s = s.slice(0,-1);
}
//remove all newlines and split by semicolon
var all = s.replace(/\n/g,'').split(';');
//console.log(all);
for(var k=0; k<all.length; ++k)
{
var match = myRegex.exec(all[k]);
if(match===null)
return false;
console.log(" match[1]: "+match[1]);
console.log(" match[2]: "+match[2]);
//break out if one pair is bad
if(! (isPlusMinus180(match[1]) && isPlusMinus90(match[2])) )
{
console.log(" one of matches out of bounds");
return false;
}
}
return true;
}
var coords = new Array('[120,80];',
'[120.33,80]',
'[180,90];[180,67];',
'[123,34];[-32,21];\n[12,-67]',
'[25,67][76,23];',
'[25,67]\n[76,23]',
'[190,33.33]',
'[180.33,33]',
'[179.87,90]',
'[179.87,91]');
var s;
for (var i = 0; i<coords.length; i++) {
s = coords[i];
console.log((i+1)+". ==== testing "+s+" ====");
console.log(" isValid? => " + isValid(s));
}