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Objective c: //this is the dictionary you start with. NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:@"name1", @"Sam",@"name2", @"Sanju",nil]; //check if the dictionary contains the key you are going to modify. In this example, @&qu...

The following will echo each line in the file C:\scripts\testFile.txt. Blank lines will not be processed. for /F "tokens=*" %%A in (C:\scripts\testFile.txt) do ( echo %%A rem do other stuff here ) More advanced example shows, how derived in FOR loop from a restricted files set...

From command line: cpan -l From a Perl script: use ExtUtils::Installed; my $inst = ExtUtils::Installed->new(); my @modules = $inst->modules();

wildcard characters are used with the SQL LIKE operator. SQL wildcards are used to search for data within a table. Wildcards in SQL are:%, _, [charlist], [^charlist] % - A substitute for zero or more characters Eg: //selects all customers with a City starting with "Lo" SEL...

Simple one-liners may be specified as command line arguments to perl using the -e switch (think "execute"): perl -e'print "Hello, World!\n"' Due to Windows quoting rules you can't use single-quoted strings but have to use one of these variants: perl -e"print qq(Hello, W...

Windows uses only double quotes to wrap command line parameters. In order to use double quotes in perl one-liner (i.e. to print a string with an interpolated variable), you have to escape them with backslashes: perl -e "my $greeting = 'Hello'; print \"$greeting, world!\n\"" T...

perl -ne'print if /foo/' file.txt Case-insensitive: perl -ne'print if /foo/i' file.txt

perl -pe"s/foo/bar/g" file.txt Or in-place: perl -i -pe's/foo/bar/g' file.txt On Windows: perl -i.bak -pe"s/foo/bar/g" file.txt

perl -lane'print "$F[0] $F[-1]"' data.txt # prints the first and the last fields of a space delimited record CSV example: perl -F, -lane'print "$F[0] $F[-1]"' data.csv

perl -ne'print if 5..10' file.txt

Without a backup copy (not supported on Windows) perl -i -pe's/foo/bar/g' file.txt With a backup copy file.txt.bak perl -i.bak -pe's/foo/bar/g' file.txt With a backup copy old_file.txt.orig in the backup subdirectory (provided the latter exists): perl -i'backup/old_*.orig' -pe's/foo/bar/g' ...

perl -0777 -ne'print "The whole file as a string: --->$_<---\n"' Note: The -0777 is just a convention. Any -0400 and above would de the same.

It is good practice to test the calling program's __name__ variable before executing your code. import sys def main(): # Your code starts here # Don't forget to provide a return code return 0 if __name__ == "__main__": sys.exit(main()) Using this pattern ens...

Adding components one after another results in a UI that's hard to use, because the components all are somewhere. The components are ordered from top to bottom, each component in a separate "row". To remedy this and provide you as developer with a possibility to layout components easily S...

I always think it is nice to have a very simple, self-contained example so that nothing is assumed when I am learning a new task. This answer is that for deleting UITableView rows. The project performs like this: This project is based on the UITableView example for Swift. Add the Code Create a ...

Weka is a collection of machine learning algorithms for data mining tasks. The algorithms can either be applied directly to a dataset or called from your own Java code. Weka contains tools for data pre-processing, classification, regression, clustering, association rules, and visualization. It is al...

Margin is one of a few CSS properties that can be set to negative values. This property can be used to overlap elements without absolute positioning. div{ display: inline; } #over{ margin-left: -20px; } <div>Base div</div> <div id="over">Overlapping div&lt...

One of the easiest ways to deploy Grails 3.x is to build an executable jar file that embeds a servlet container (Tomcat, Undertow, etc) with the application. Modify build.gradle: // Remove or comment out the war plugin: // apply plugin:"war" // Enable the executable jar: springBoot ...

3.0 The => operator has the same precedence as the assignment operator = and is right-associative. It is used to declare lambda expressions and also it is widely used with LINQ Queries: string[] words = { "cherry", "apple", "blueberry" }; int shortestWordLength...

genRandom creates a stream of random numbers that has a one in four chance of terminating each time it's called. def genRandom: Stream[String] = { val random = scala.util.Random.nextFloat() println(s"Random value is: $random") if (random < 0.25) { Stream.empty[String] ...