Re: Is there a more elegant way to do null checks?

The ! operator is the best

${(patient.name.first)!"<Not Entered>"}

[#list (patient.diagnoses)![] as dx]
  ${(dx.code)!"<Unknown>"}
[/#list]

[#if (template.scripts.inline.head)!{}?has_content]    
  Do something
[/#if]

For the last one there I am not 100% on the order of precedence, you may need an extra paren before the ?


-----Original Message-----
From: Jan Haderka [mailto:[email protected]] 
Sent: Wednesday, March 24, 2010 4:52 PM
To: FreeMarker-user
Subject: Re: [FreeMarker-user] Is there a more elegant way to do null checks?


When I rewrote my tag files as macros, I produced a lot of bloated template
code like so:

[#if (template?? && template.scripts?? && template.scripts.inline?? &&
template.scripts.inline.head??)]do something[/#if]

Is there a more elegant way to check if the head value is empty? I have

I'm not an expert, but would not something like:

[#if (template.scripts.inline.head)??]do something[/#if]

do?

Jan

------------------------------------------------------------------------------
Download Intel&#174; Parallel Studio Eval
Try the new software tools for yourself. Speed compiling, find bugs
proactively, and fine-tune applications for parallel performance.
See why Intel Parallel Studio got high marks during beta.
http://p.sf.net/sfu/intel-sw-dev
_______________________________________________
FreeMarker-user mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/freemarker-user


------------------------------------------------------------------------------
Download Intel&#174; Parallel Studio Eval
Try the new software tools for yourself. Speed compiling, find bugs
proactively, and fine-tune applications for parallel performance.
See why Intel Parallel Studio got high marks during beta.
http://p.sf.net/sfu/intel-sw-dev