Convert JavaScript string to JavaScript literal - javascript

In Chrome, when you right-click a string on the console, you'll see "copy string as javascript literal" option. This is what I want to have now, in JavaScript.
For example, let's say I have the following text content:
console.log('hoge');
My question is, how can I get something below from the above?
"console.log('hoge');"
I want to do this because, I have a mega bytes of webpack-generated long JavaScript content, and for a reason I need to eval() the script on an other environment, so I want to copy-and-paste the JavaScript literal text to inside the "eval()". (you may suggest exchanging the data not with the literal but with json (json.stringify/parse), I know, but I just prefer the literal way for now)
So is it possible? Thanks.

After noting the advice regarding the security weakness inherent in using eval (see: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval)
You can achieve what you want by enclosing the entire literal code inside back-ticks and using the resulting string as the eval argument. back tick quotted strings can include line breaks so you should be able to pass your entire code block inside a single set.
Working snippet.
console.log('hoge');
console.log('another hoge');
eval(`console.log('hoge');
console.log('another hoge')`);

You can easily enclose Javascript in backticks to get a template literal:
eval(`console.log('hoge')`)
But you should also escape backticks inside the Javascript code to handle situations like this:
eval(`console.log(`hoge`)`) // SyntaxError
As a solution, you can use this bash one-liner:
sed 's/`/\\`/g' | xargs -0 printf 'eval(`%s`)'
Invoke the command by pressing Enter.
Paste in the Javascript you want to escape and press Enter again.
Press Ctrl+D to finish input.
You will get valid eval() function call with escaped template literal on the output.
You can assign this one-liner command to an alias for easy use:
alias js_eval_literal="sed '"'s/`/\\`/g'"' | xargs -0 printf '"'eval(`%s`)'"'"

Related

CL-WHO is always starting with a single quote

My issue is that CL-WHO begins each expression with a single quotation market when it turns the Lisp S-expressions into html output. This is okay most of the time, but it is an issue since I am linking my file to an external javascript file. I am trying to make this project simple, and since none of the javascript developers on my team know Common Lisp, using parenscript is likely out of the equation. Here is an example of my issue and one of the errors in my program:
:onclick "alertUser('id')"
When a particular element is pressed within the html document, this should trigger a JavaScript function called alertUser, and the id of the tag should be passed to the JavaScript function as an argument. But no matter what I do, CL-WHO will convert that string into single quotation marks, so I end up with an invalid expression. Here is what that code converts to:
onclick='alertUser('id')'>
Everything is a single quotation so 'alertUser(' is passed as the first string which is obviously invalid and I receive a syntax area in my developer tools. I thought that I could solve this problem by using the format function with escape characters. This would equate to:
CL-USER> (format t "\"alertUser('id')\"")
"alertUser('id')"
NIL
CL-USER>
But when I try that with CL-WHO:
:onclick (format nil "\"alertUser('id')\"")
That translates to:
onclick='"alertUser('locos-tacos-order')"'>
Which is also invalid html. As you can see, CL-WHO will start with a single quote no matter what. Next I tried the CL-WHO fmt function:
:onclick (fmt "\"alertUser('locos-tacos-order')\"")
When I use the fmt function it gets rid of my :onclick expression entirely when it is converted to html!:
id='id'"alertUser('id')">
Lastly I tried the str function, and got similarly invalid output to my original attempt:
onclick='"alertUser('id')"'
Obviously if I code this in pure html it will look like:
onclick="alertUser('id')">
Which is valid.
My question is simply how do I enable CL-WHO to use double quotation marks in these situations instead of single quotation marks?
#jkiiski was has the correct answer in the comments underneath my question, but I wanted to post the answer so that anyone with a similar issue in the future can resolve the problem. As #jkiiski said, there is a variable called ATTRIBUTE-QUOTE-CHAR in the cl-who package that defaults to #\'. You can simply set that variable to #\" instead in order for the default quotations used to be double quotation marks:
(setf *attribute-quote-char* #\")
After adding that line of code near the top of the file my html defaults to:
onclick="alertUser('id')"
and now the javascript can execute properly. Credit to #jkiiski for a correct answer.

How to Use ES6 Template Literals in Freemarker? [duplicate]

I'm trying to use Freemarker in conjunction with jQuery Templates.
Both frameworks use dollar sign/curly brackets to identify expressions for substitution (or as they're called in freemarker, "interpolations") , e.g. ${person.name} .
So when I define a jQuery Template with expressions in that syntax, Freemarker tries to interpret them (and fails).
I've tried various combinations of escaping the ${ sequence to pass it through Freemarker to no avail - \${, \$\{, $\{, etc.
Inserting a freemarker comment in between the dollar and the curly (e.g. $<#-- -->{expression}) DOES work - but I'm looking for a more concise and elegant solution.
Is there a simpler way to get a Freemarker template to output the character sequence ${?
This should print ${person.name}:
${r"${person.name}"}
From the freemarker docs
A special kind of string literals is the raw string literals. In raw string literals, backslash and ${ have no special meaning, they are considered as plain characters. To indicate that a string literal is a raw string literal, you have to put an r directly before the opening quotation mark or apostrophe-quote
For longer sections without FreeMarker markup, use <#noparse>...</#noparse>.
Starting with FreeMarker 2.3.28, configure FreeMarker to use square bracket syntax ([=exp]) instead of brace syntax (${exp}) by setting the interpolation_syntax configuration option to square_bracket.
Note that unlike the tag syntax, the interpolation syntax cannot be specified inside the template. Changing the interpolation syntax requires calling the Java API:
Configuration cfg;
// ...
cfg.setInterpolationSyntax(SQUARE_BRACKET_INTERPOLATION_SYNTAX);
Then FreeMarker will consider ${exp} to be static text.
Do not confuse interpolation syntax with tag syntax, which also can have square_bracket value, but is independent of the interpolation syntax.
When using FreeMarker-based file PreProcessor (FMPP), either configure the setting via config.fmpp or on the command-line, such as:
fmpp --verbose --interpolation-syntax squareBracket ...
This will call the appropriate Java API prior to processing the file.
See also:
https://freemarker.apache.org/docs/dgui_misc_alternativesyntax.html
http://fmpp.sourceforge.net/settings.html#templateSyntax
Another option is to use #include with parse=false option. That is, put your jQuery Templates into the separate include page and use parse=false so that freemarker doesn't try and parse it.
This would be a good option when the templates are larger and contain double quotes.
I had to spent some time to figure out the following scenarios to escape ${expression} -
In Freemarker assignment:
<#assign var = r"${expression}">
In html attribute:
Some link
In Freemarker concatenation:
<#assign x = "something&"+r"${expression}"/>
If ${ is your only problem, then you could use the alternate syntax in the jQuery Templates plugin like this: {{= person.name}}
Maybe a little cleaner than escaping it.
Did you try $$?
I found from the Freemarker manual that ${r"${person.name}"} will print out ${person.name} without attempting to render it.
Perhaps you should also take a look at Freemarker escaping freemarker
I can confirm that the
${r"${item.id}"}
is the correct way as an example.
So I kinda full example will look like
<span> Remove </span>
and the output will be :
<span> Remove </span>
In the case when you want to use non-raw strings so that you can escape double quotes, apostrophes, etc, you can do the following:
Imagine that you want to use the string ${Hello}-"My friend's friend" inside of a string. You cannot do that with raw strings. What I have used that works is:
${"\x0024{Hello}-\"My friend's friend\""}
I have not escaped the apostrophe since I used double quotes.

A way to automatically enclosure quotes inside string containing code (RegExp maybe?)

Is there a way to automatically enclosure all quotes inside the string of js-code which contains other strings by itself? I just failed to make a RegExp valuable to identify all the quotes properly. Because in some cases (blocks of code generated by script) there strings of code like:
$(".class1.class2:contains('text')").param(s1+s2+"-"+s3+"_"+i)...
var r=new RegExp("blabla[qwer]\\'\\w+\\d\\'");
//etc.
More complex actually and less readable =)
But anyways is there a way to get rid of constant http/ajax/json requests and make code to work without injection but via eval? It's not intended to be used in outer net so it's safe, dont tell me anything 'bout eval =) The main problem: how to make enclosurement of quotes inside the string...
Edit:
Sorry i just don't know how to say it in English, so by enclosurement i mean insertion of a specific symbol before char which has dual meaning to clarify it's definition for compiler or machine-interpreter.
Example1: ('first_part_of_string enclosured_quote=\' second_part_of_string')
Example2: `<- these symbols don't get interpreted as code-markers because of enclosurement ->`
Sure, here it is with single quotes:
'
$(".class1.class2:contains(\'text\')").param(s1+s2+"-"+s3+"_"+i)...
var r=new RegExp("blabla[qwer]\\\\\'\\\w+\\\d\\\\\'");
'
here it is with double quotes:
"
$(\".class1.class2:contains('text')\").param(s1+s2+\"-\"+s3+\"_\"+i)...
var r=new RegExp(\"blabla[qwer]\\\\'\\\\w+\\\\d\\\\'\");
"
You can use the Mega-String tool to do this automatically
I used the single / double quote option from the Other category..

How to assign large string to a variable without ILLEGAL Token error?

I need to assign a long string (4 pages worth of text) to a variable, so far I've been doing it like this
var myText = "[SOME] Text goes \
.. here ? and 'there' \
is more ( to \
come etc. !)";
slashes at the end need to be added to all of the text, and I can't imagine how long this will take to do manually. Also, I get ILLEGAL error for some reason I don't understand for the first line.
Therefore I wanted to find out the best way to handle this situation. I was looking into solutions of passing in a .txt file, but would rather do it as a really long string (this is not a production app). Also string shown in example is random, showing that there can be a lot of various characters in it that need to be accounted for.
You have to concatenate the string:
var t = ""
+"text line 1"
...
+"text line n"
But I would put the text in a text file and read it using xhr (on client) or io (on server).
You cannot have a multiline string definition in javascript but you have several options :
save your text in a file and read this file from your program
use the multiline npm module which propose a hack to use function comments as multiline string definitions
use ES6 multi-line template strings notation, which have multi-line support - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/template_strings#Multi-line_strings
saving the text in a file would seem to me as the preferred option in your case since the text seem to be very long an potentially coming from an untrusted source. You do not want the pasted text to close the string and start doing innapropriate function calls.

Escaping quotation marks in PHP for JavaScript function argument

I'm having trouble escaping a quotation mark in PHP.
I have a table of products and each row has an onclick function, with the name of the product as the argument.
The name contains the length which is measured in inches, so the name contains a quotation mark. I wrapped an addslashes() around the string. This adds a backslash before the quotation mark but for some reason it doesn't seem to escape the character!
Here's a snippet of my code:
<?$desc1 = addslashes($row['Desc1']);?>
<tr class='tableRow' onclick='afterProductSelection("<?=$desc1?>")'>
<td><?=$row['Desc1']?></td>
When I inspect element in Google Chrome, the colour of the syntax indicates that this has not been escaped, clicking on it gives me a syntax error.
Probably something simple that I'm missing. Hope you can help!
There are a lot of different cases where you need to escape a string. addslashes() is the wrong answer to pretty much all of them.
The addslashes() function is an obsolete hang-over from PHP's early days; it is not suitable for any escaping. Don't use it. Ever. For anything.
In your particular case, since you're creating Javascript data from PHP, use json_encode().
json_encode() will take a PHP variable (whether it's a string, array, object or whatever) and convert it into a JSON string. A JSON string is basically fully escaped Javascript variable, including the quotes around your strings, etc. This is what you need to do.
The addslashes() function is an obsolete hang-over from PHP's early days; it is not suitable for any escaping. Don't use it. Ever. For anything. -Spudley
I think the function you're looking for is htmlentities()
<?=htmlentities($desc1, ENT_QUOTES)?>
http://ca1.php.net/htmlentities
You are generating a JavaScript string encoded as HTML so you need to encode twice:
Use json_encode() to generate the string
Use htmlspecialchars() to encode as HTML
Use json_encode to output variables from the backend in JavaScript:
<tr onclick='afterProductSelection(<? print json_encode($desc1); ?>)'>
N.B.: For string output there is no need for extra quotes.

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