i am new to Kotlin
I would like to iterate through my map and check if there is line break anywhere and if so return false, what would be the best approach. I am not sure if i can use mathches , but yeh basically if. lets say there is a string value "Hello" +c /n + "world": i would like to return false
fun isLineBreakExist(languageMap: MultiLanguageString){
languageMap.forEach { (value) -> value.matches("") }
}
}
Related
validValueType.ValueTypeGroup
["\"is_enabled\": false", "\"value\":\"OUT\""]
failedRecord.record
{"email":"test#gmail.com","source":"web","value":"OUT","reate_date":"2022-09-29T03:42:09.976-05:00","is_undeliverable":false}
fun publishAlert(failedRecord: Record<String>) {
if (validValueType.ValueTypeGroup.contains(failedRecord.record)) {
// do stuff
} else {
// no match do other stuff
}
}
In the list above there are two strings I want to check for when this function receives a record.
The failedRecord.record string does contain what I want "value":"OUT" and it's also within the list above. So why is contains not working here? it keeps bouncing out to the else statement.
You can use any() in the list and pass a predicate:
{x -> searchString.contains(x)}
The searchString.contains() will search x as a substring inside searchString for each x representing the elements in the list
var list = listOf("\"is_enabled\": false", "\"value\":\"OUT\"")
println(list)
println(list::class.qualifiedName)
println() // empty newline
var searchString = "{\"email\":\"test#gmail.com\",\"source\":\"web\",\"value\":\"OUT\",\"create_date\":\"2022-09-29T03:42:09.976-05:00\",\"is_undeliverable\":false}";
println(searchString)
println(searchString::class.qualifiedName)
println() // empty newline
println(list.any{x -> searchString.contains(x)});
Output
["is_enabled": false, "value":"OUT"]
java.util.Arrays.ArrayList
{"email":"test#gmail.com","source":"web","value":"OUT","create_date":"2022-09-29T03:42:09.976-05:00","is_undeliverable":false}
kotlin.String
true
I am trying to replace a few sub strings inside a string. But my code doesn't seem to work.
val listOfMaleWords = listOf(" him", " he", " his")
val listOfFemaleWords = listOf(" her", " she", " her")
fun modifyIdeaForGender(rawIdea : String, desiredGender : String): String {
var theRawIdea = rawIdea
if (desiredGender == "FEMALE") {
println("desired gender is FEMALE")
listOfMaleWords.forEachIndexed { index, element ->
theRawIdea.replace(element, listOfFemaleWords[index])
}
} else {
println("desired gender is MALE")
listOfFemaleWords.forEachIndexed { index, element ->
theRawIdea.replace(element, listOfMaleWords[index])
}
}
return theRawIdea
}
fun main() {
var sampleString : String = "Tell him, he is special"
println(modifyIdeaForGender(sampleString, "FEMALE"))
}
Expected Output :
"Tell her, she is special"
Current Output :
"Tell him, he is special" // no change
Whats wrong with my code? The current output doesn't replace the string characters at all.
replace returns a new String that you are discarding immediately. It does not mutate theRawIdea itself, so you should assign it back to theRawIdea yourself. For example:
theRawIdea = theRawIdea.replace(element, listOfFemaleWords[index])
Though this would modify theRawIdea as you desire, it wouldn't replace the pronouns correctly. Once it replaces the "him"s with "her"s, it would try to replace the "he"s with "she"s. But note that "he" a substring of "her"! So this would produce:
Tell sher, she is special
This could be fixed by reordering the lists, putting the "he"-"she" pair first, or by using regex, adding \b word boundary anchors around the words:
// note that you should not have spaces before the words if you decide to use \b
val listOfMaleWords = listOf("him", "he", "his")
val listOfFemaleWords = listOf("her", "she", "her")
...
theRawIdea = theRawIdea.replace("\\b$element\\b".toRegex(), listOfFemaleWords[index])
Note that this doesn't account for capitalisation or the fact that changing from female gender pronouns to male ones is inherently broken. Your current code would change all her to him. It would require some more complicated natural language processing to accurately do this task in general.
Taking all that into account, I've rewritten your code with zip:
fun modifyMaleIdeaToFemaleGender(rawIdea : String): String {
var theRawIdea = rawIdea
// if you really want to do the broken female to male case, then this would be
// listOfFemaleWords zip listOfMaleWords
// and the loop below can stay the same
val zipped = listOfMaleWords zip listOfFemaleWords
zipped.forEach { (target, replacement) ->
theRawIdea = theRawIdea.replace("\\b$target\\b".toRegex(), replacement)
}
return theRawIdea
}
You can also use fold to avoid reassigning theRawIdea:
fun modifyIdeaToFemaleGender(rawIdea : String): String {
val zipped = listOfMaleWords zip listOfFemaleWords
return zipped.fold(rawIdea) { acc, (target, replacement) ->
acc.replace("\\b$target\\b".toRegex(), replacement)
}
}
Your code assumes that the replace() method performs an in-place mutation of the string. However, the string with the replaced values are returned by the replace(). So you need to change your code to contain something like:
theRawIdea = theRawIdea.replace(element, listOfFemaleWords[index])
To do this, you will have to use a conventional loop instead of listOfMaleWords.forEachIndexed style looping.
i'm trying to get multiple input from user and i'm using readlint()!! following by for loop when i go try to print those input back it only shows one output which is the last one...
And i have tried .split(' ') method which is kinda better than for Loop trick but i want my program more better..
1- it take input from new line(for Multiple inputs)
2- it print out all user input
here's my code and it prints out in one line
fun getTheData() {
try{
val(a,b,c) = readLine()!!.split(' ')
println("$a , $b, $c")
}catch (ex: IndexOutOfBoundsException){
println("invalid")
}
}
Here you're only reading one line.
The split() function simply splits your single line into multiple parts separated by a single whitespace.
In short, if you input 1 2 3 in one line, it will print the 3 numbers. However, if you input several lines, you'll only get the first line, as you never read other lines (only one call to readLine()).
In order to read more lines, you do need some sort of loop, like:
fun main() {
while(true) {
val line = readLine()!!
println(line)
}
}
While exploring the documented example raised in this perl6 question that was asked here recently, I found that the final implementation option - (my interpretation of the example is that it provides three different ways to do something) - doesn't work. Running this;
class HTTP::Header does Associative {
has %!fields handles <iterator list kv keys values>;
sub normalize-key ($key) { $key.subst(/\w+/, *.tc, :g) }
method EXISTS-KEY ($key) { %!fields{normalize-key $key}:exists }
method DELETE-KEY ($key) { %!fields{normalize-key $key}:delete }
method push (*#_) { %!fields.push: #_ }
multi method AT-KEY (::?CLASS:D: $key) is rw {
my $element := %!fields{normalize-key $key};
Proxy.new(
FETCH => method () { $element },
STORE => method ($value) {
$element = do given $value».split(/',' \s+/).flat {
when 1 { .[0] } # a single value is stored as a string
default { .Array } # multiple values are stored as an array
}
}
);
}
}
my $header = HTTP::Header.new;
say $header.WHAT; #-> (Header)
$header<Accept> = "text/plain";
$header{'Accept-' X~ <Charset Encoding Language>} = <utf-8 gzip en>;
$header.push('Accept-Language' => "fr"); # like .push on a Hash
say $header<Accept-Language>.perl; #-> $["en", "fr"]
... produces the expected output. Note that the third last line with the X meta-operator assigns a literal list (built with angle brackets) to a hash slice (given a flexible definition of "hash"). My understanding is this results in three seperate calls to method AT-KEY each with a single string argument (apart from self) and therefore does not exersise the default clause of the given statement. Is that correct?
When I invent a use case that excersises that part of the code, it appears to fail;
... as above ...
$header<Accept> = "text/plain";
$header{'Accept-' X~ <Charset Encoding Language>} = <utf-8 gzip en>;
$header{'Accept-Language'} = "en, fr, cz";
say $header<Accept-Language>.perl; #-> ["en", "fr", "cz"] ??
# outputs
(Header)
This Seq has already been iterated, and its values consumed
(you might solve this by adding .cache on usages of the Seq, or
by assigning the Seq into an array)
in block at ./hhorig.pl line 20
in method <anon> at ./hhorig.pl line 18
in block <unit> at ./hhorig.pl line 32
The error message provides an awesome explanation - the topic is a sequence produced by the split and is now spent and hence can't be referenced in the when and/or default clauses.
Have I correctly "lifted" and implemented the example? Is my invented use case of several language codes in the one string wrong or is the example code wrong/out-of-date? I say out-of-date as my recollection is that Seq's came along pretty late in the perl6 development process - so perhaps, this code used to work but doesn't now. Can anyone clarify/confirm?
Finally, taking the error message into account, the following code appears to solve the problem;
... as above ...
STORE => method ($value) {
my #values = $value».split(/',' \s+/) ;
$element = do given #values.flat {
when 1 { $value } # a single value is stored as a string
default { #values } # multiple values are stored as an array
}
}
... but is it an exact equivalent?
That code works now (Rakudo 2018.04) and prints
$["en", "fr", "cz"]
as intended. It was probably a bug which was eventually solved.
I got this parameter:
$objDbCmd.Parameters.Add("#telephone", [System.Data.SqlDbType]::VarChar, 18) | Out-Null;
$objDbCmd.Parameters["#telephone"].Value = $objUser.Telephone;
Where the string $objUser.Telephone can be empty. If it's empty, how can I convert it to [DBNull]::Value?
I tried:
if ([string]:IsNullOrEmpty($objUser.Telephone)) { $objUser.Telephone = [DBNull]::Value };
But that gives me the error:
Exception calling "ExecuteNonQuery" with "0" argument(s): "Failed to convert parameter value from a ResultPropertyValueCollection to a String."
And if I convert it to a string, it inserts an empty string "", and not DBNull.
How can this be accomplished?
Thanks.
In PowerShell, you can treat null/empty strings as a boolean.
$x = $null
if ($x) { 'this wont print' }
$x = ""
if ($x) { 'this wont print' }
$x = "blah"
if ($x) { 'this will' }
So.... having said that you can do:
$Parameter.Value = $(if ($x) { $x } else { [DBNull]::Value })
But I'd much rather wrap this up in a function like:
function CatchNull([String]$x) {
if ($x) { $x } else { [DBNull]::Value }
}
I don't know about powershell, but in C# I would do something like this:
if ([string]::IsNullOrEmpty($objUser.Telephone))
{
$objDbCmd.Parameters["#telephone"].Value = [DBNull]::Value;
}
else
{
$objDbCmd.Parameters["#telephone"].Value = $objUser.Telephone;
}
Always append +"" at the end of db values...
$command.Parameters["#EmployeeType"].Value= $ADResult.EmployeeType + ""
Many years later, let me clarify:
Josh's answer shows a helpful simplification for testing strings for emptiness (relying on PowerShell's implicit to-Boolean conversion[1]), but it is unrelated to Tommy's (the OP's) problem.
Instead, the error message
"Failed to convert parameter value from a ResultPropertyValueCollection to a String."
implies that it is the non-null case that caused the problem, because $objDbCmd.Parameters["#telephone"].Value expects either a string value or [DBNull]::Value, whereas $objUser.Telephone is of type [ResultPropertyValueCollection], i.e. a collection of values.
Thus, in the non-null case, a string value must be assigned, which must be derived from the collection; one option is to take the first collection element's value, another would be to join all values with a separator to form a single string, using, e.g., [string]::Join(';', $objUser.Telephone) or, if joining the elements with spaces is acceptable (not a good idea with multiple phone numbers), simply with "$($objUser.Telephone)".[2]
Detecting an empty collection via [string]:IsNullOrEmpty() actually worked, despite the type mismatch, due to how PowerShell implicitly stringifies collections when passing a value to a [string] typed method parameter.[2]
Similarly, using implicit to-Boolean conversion works as expected with collections too: an empty collection evaluates to $false, a non-empty one to $true (as long as there are either at least two elements or the only element by itself would be considered $true[1])
Therefore, one solution is to use the first telephone number entry:
$objDbCmd.Parameters["#telephone"].Value = if ($objUser.Telephone) {
$objUser.Telephone[0].ToString() # use first entry
} else {
[DBNull]::Value
}
Note: If $objUser.Telephone[0] directly returns a [string], you can omit the .ToString() call.
In PowerShell v7+ you can alternatively shorten the statement via a ternary conditional:
$objDbCmd.Parameters["#telephone"].Value =
$objUser.Telephone ? $objUser.Telephone[0].ToString() : [DBNull]::Value
[1] For a comprehensive summary of PowerShell's automatic to-Boolean conversions, see the bottom section of this answer.
[2] When implicitly converting a collection to a string, PowerShell joins the stringified elements of a collection with a single space as the separator by default; you can override the separator with the automatic $OFS variable, but that is rarely done in practice; e.g., array 'foo', 'bar' is converted to 'foo bar'; note that this conversion does not apply when you call the collection's .ToString() method explicitly, but it does apply inside expandable (interpolating) strings, e.g., "$array".