heredoc

问题 This question already has answers here : Using variables inside a bash heredoc (3 answers) Closed 9 months ago . In the code below, variable X is output normally. # cat a.sh X=world echo 'hello' $X # cat a.sh | bash hello world But, using here doc, variable X is not displayed. # cat <<EOF | bash > X=world > echo 'hello' $X > EOF hello # bash -s <<EOF > X=world > echo 'hello' $X > EOF hello What made this difference? 回答1: You can see what happens when you remove the |bash X=oldvalue cat <<EOF

问题 substr($obj_strptime,index($strptime,"sub")+6,0) = <<'ESQ'; shift; # package .... .... ESQ What is this ESQ and what is it doing here? Please help me understand these statements. 回答1: It marks the end of a here-doc section. EOF is more traditional than ESQ though. 回答2: This construct is known as a here-doc (because you're getting standard input from a document here rather than an external document on the file system somewhere). It basically reads everything from the next line up to but

问题 I'm new to PHP and don't understand what the point of <<<_END is. Could someone please explain when this should be used? I've looked at various examples and they all seem to have HTML embedded within them. But I can use HTML without the <<<_END tags, so why should I use them? I tried searching the manual, but I keep finding the end() method for arrays. 回答1: It's the start of a heredoc. you can do: $data = <<< _END You can write anything you want in between the start and end _END; _END can be

问题 I'm new to PHP and don't understand what the point of <<<_END is. Could someone please explain when this should be used? I've looked at various examples and they all seem to have HTML embedded within them. But I can use HTML without the <<<_END tags, so why should I use them? I tried searching the manual, but I keep finding the end() method for arrays. 回答1: It's the start of a heredoc. you can do: $data = <<< _END You can write anything you want in between the start and end _END; _END can be

问题 This question already has answers here : Java multiline string (40 answers) Closed 4 years ago . For JAVA development I need writing to a files with strings like "\r\t\n <>", because from Java I want writing a PHP file. If you can't understand look at this example: BufferedWriter buffW = new BufferedWriter(fileW); buffW.write("<?php\n\n\tclass MyClass {\n\tpublic function test()\n}\n}\n?>"); This is mess a code, I want to write a clean such as PHP can do, but can't find on Java alternative

问题 This question already has answers here : Java multiline string (40 answers) Closed 4 years ago . I need to work with long strings containing line breaks in Java. Those are for HTML generation, but it is not the most important here. I'm aware Java is cripple in a way it doesn't have heredocs . But there are other mechanisms I could use: 1) String concatenation (or StringBuilders), not very readable and copy-pasteable. 2) Storing strings in .properties files, either not very readable, but with

问题 I would like a Bash script that can take input from a file or stdin, much like grep , for example $ cat hw.txt Hello world $ grep wor hw.txt Hello world $ echo 'Hello world' | grep wor Hello world $ grep wor <<< 'Hello world' Hello world all works beautifully. However with the following script read b < "${1-/dev/stdin}" echo $b It fails if using a herestring $ hw.sh hw.txt Hello world $ echo 'Hello world' | hw.sh Hello world $ hw.sh <<< 'Hello world' /opt/a/hw.sh: line 1: /dev/stdin: No such

问题 Update- Thanks for all the responses. This Q is getting kind of messy, so I started a sequel if anyone's interested. I was throwing together a quick script for a friend and stumbled across a really simple way of doing templating in PHP. Basically, the idea is to parse the html document as a heredoc string, so variables inside of it will be expanded by PHP. A passthrough function allows for expression evaluation and function and static method calls within the string: function passthrough($s)

问题 The following snippet is causing an "PHP Parse error: syntax error, unexpected $end in /Applications/MAMP/htdocs3/nettuts/PHP/PDO for Database Access/htdocs/view_users02.php on line 39" I've looked around the site and google but didn't find an exact solution. foreach($DBH->query($sql) as $row){ $output = "<tr><td align='left'>" . $row["name"] . "</td><td align='left'>" . $row["dr"] . "</td></tr>"; // echo '<tr><td align="left">' . $row['name'] . '</td><td align="left">' . $row['dr'] . '</td><

问题 I'm using Python with -c to execute a one-liner loop, i.e.: $ python -c "for r in range(10): print 'rob'" This works fine. However, if I import a module before the for loop, I get a syntax error: $ python -c "import sys; for r in range(10): print 'rob'" File "<string>", line 1 import sys; for r in range(10): print 'rob' ^ SyntaxError: invalid syntax Any idea how this can be fixed? It's important to me to have this as a one-liner so that I can include it in a Makefile. 回答1: you could do echo