concatenation

Consider the following line of code: <?php $x = 10; $y = 7; echo '10 - 7 = '.$x-$y; ?> The output of that is 3, which is the expected result of the calculation $x-$y. However, the expected output is: 10 - 7 = 3 My question therefore is, what happened to the string that I'm concatenating with the calculation? I know that in order to produce the result I expected, I need to enclose the arithmetic operation in parenthesis: <?php $x = 10; $y = 7; echo '10 - 7 = '.($x-$y); ?> outputs 10 - 7 = 3 But since PHP does not complain about the original code, I'm left wondering what the logic behind the

This question already has an answer here: string concatenation in css 5 answers How can I concatenate the CSS attr() selector with static text in a url() field? The HTML I use: <div image='/Require/static.png'></div> //Example 2 <div image='static.png'></div> //Example 3, 4, 5 For example: //image attribute contains the image name (and prefix location when needed, see example 2) div[image]:before { background-image: url('/Image/static.png'); //Works background-image: url(attr(image)); // Works background-image: url('/Image/' attr(image)); //Fails background-image: url('/Image/' #attr(image));

This question already has an answer here: Use dynamic variable names in JavaScript 15 answers Is it possible to set a variable by concatenating two strings together to form the name? If at all possible I'd like to determine what variable to set based on the class names of the objects that the user clicks. I know I can hard code a bunch of if/else if statements, but it would be really cool if I could reference the variables indirectly. I was thinking something like this: var owner_read; var group_read; function setVariableIndirectly(object){ var second = object.className; // returns "read" var

I am working with Hadoop 0.20.2 and would like to concatenate two files into one using the -cat shell command if possible (source: http://hadoop.apache.org/common/docs/r0.19.2/hdfs_shell.html ) Here is the command I'm submitting (names have been changed): **/path/path/path/hadoop-0.20.2> bin/hadoop fs -cat /user/username/folder/csv1.csv /user/username/folder/csv2.csv > /user/username/folder/outputdirectory/** It returns bash: /user/username/folder/outputdirectory/: No such file or directory I also tried creating that directory and then running it again -- i still got the 'no such file or

I saw this response for extending one array with another so I tried: console.log(['a', 'b'].push.apply(['c', 'd'])); but it prints: 2 shouldn't it print: ['a', 'b', 'c', 'd'] if not what was i doing wrong? Felix Kling if not what was i doing wrong? First of all, .push returns the new length of the array: var arr = [1, 1, 1]; console.log(arr.push(1)); // 4 console.log(arr); // [1, 1, 1, 1] Second, .apply needs two arguments: The object you want to apply the function to, and an array of arguments. You only pass a single argument, so your code is basically equivalent to: ['c', 'd'].push() I.e.

This question already has an answer here: How to concatenate text from multiple rows into a single text string in SQL server? 47 answers I'm porting an application I originally wrote to run on Apache using PHP and a MySQL database. One of the queries used the MySQL functions of Concat_WS and Group_Concat to first concatenate a few different columns into one string, and then concatenate all items that were grouped together by the Group_By clause. As an example: ID Name Candy 1 John M&Ms 1 John KitKat The query: Select Group_Concat(Concat_WS('-',Name, Candy) Separator '00--00') as UserCandy From