In Freemarker you can
<p>${my_var!}</p>
to avoid having an error message if my_var is not defined, and
<p>${my_var!"this is undefined!"}</p>
to set a defaut value for my_var if it is not defined.
What with Velocity? Do you also have a compact syntaxe or do you have to do a if/else statement?
Found an answer here :
Velocity nulls and empty strings
solution with velocity :
<p>$!my_var</p>
Related
I would like to get some parameters from IPOPT, like for instance,
Using Ipopt
k = barrier_tol_factor
I know this doesn't work. Does anyone now how I can access thoes?
I tried with
Ipopt.barrier_tol_factor
It seems getting the current option value is tricky. But you can set this option and then the value should be known:
Ipopt.AddIpoptNumOption(solver, "barrier_tol_factor", 15.0)
BTW the default value is 10.0.
In Dart/Flutter, suppose you have an instance a of Class Y.
Class Y has a property, property1.
You want to print that property using string interpolation like so:
print('the thing I want to see in the console is: $a.property1');
But you can't even finish typing that in without getting an error.
The only way I can get it to work is by doing this:
var temp = a.property1;
print ('the thing I want to see in the console is: $temp');
I haven't found the answer online... and me thinks there must be a way to just do it directly without having to create a variable first.
You need to enclose the property in curly braces:
print('the thing I want to see in the console is: ${a.property}');
That will then print the value of a.property.
It seems you can also do this, but it doesn't seem to be documented anywhere:
print('..... $a.$property1');
I am trying to use an if statement with a variable in my expression and I get no results. The variable works when I use the variable on it's own but when used with the if I get no results.
I have tried:
if(OrderQtr='Apr-Jun 2018',$(vAvgOrderCost),0)
if(OrderQtr='Apr-Jun 2018',sum($(vAvgOrderCost)),0)
sum($(vAvgOrderCost)if(OrderQtr='Apr-Jun 2018',0))
Nothing seems to work. Thanks
Variables in QlikView are used as a text replace feature, so be carefull. If your variable hold a value like 1,345 an expression like "if(OrderQtr='Apr-Jun 2018',$(vAvgOrderCost),0)" will be translated into "if(OrderQtr='Apr-Jun 2018',1,345,0)" which by itself will be a syntax error.
Something like :
Num(if(OrderQtr='Apr-Jun 2018','$(vAvgOrderCost)','0'))
would be a safe way to go.
the if() syntax should work like this if(test,true,false)
So looking at your examples I suspect this is what you are trying to do
sum(if(OrderQtr='Apr-Jun 2018',$(vAvgOrderCost),0))
I have a HashMap in my bean:
HashMap<String, SomeObject> someHashMap;
Then in the velocity template I need to access the HashMap with a value that I have in velocity from other source (in fact I have many keys not only one that's why I need to get the values this way):
$key
How can I access the hashmap with this key? I'm trying:
$someHashMap.get($key)
and
${someHashMap.get($key)}
But those two only write the same thing to the output, meaning that with the first line I literally get:
$someHashMap.get($key)
In the webpage.
Which is the correct way/syntaxis to do this?
Thanks!
Both are correct syntax, and they should work.
Does $key have the right value? Print it.
Does $someHashMap indeed point to the map? Print it. If not, perhaps you forgot to put in the VelocityContext being used.
Is the value stored under that key null? The default behavior of Velocity is to print out the code that was called when the outcome is null. To make it not do that, use the silent notation: $!{someHashMap.get($key)}
I had this exact same problem. In my case I tried to do this:
$map.get($locale)
where $locale is e.g. "fi_FI". I solved it by adding quotes inside the brackets:
$map.get("$locale")
I'm not sure, but I think the rationale goes like this:
$map.get( $locale ) -> $map.get( fi_FI ) -> Velocity gets confused
$map.get("$locale") -> $map.get("fi_FI") -> Velocity retrieves correct value
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.