Creating a freemarker macro with optional nested content? - freemarker

What is the proper way to create a macro that can be used with or without nested content? e.g.
<#myMacro/>
<#myMacro>my nested content</#myMacro>
Is there something like this? Or something else?
<#macro myMacro>
<#if ??????>
Before nested content
<#nested/>
After nested content
<#else/>
Nothing nested here
</#if>
</#macro>

The nested content is assigned to a variable and then this variable is checked if it has any content. The variable is then sent to the output instead of using another nested directive to avoid the content being processed twice.
<#macro myMacro>
<#assign nested><#nested/></#assign>
<#if nested?has_content>
Before nested content
${nested}
After nested content
<#else/>
Nothing nested here
</#if>
</#macro>

Related

Trying to generate a string that becomes a variable name in Freemarker or a "derived variable name"

I'm using a data-directive or list to pull in several values, of which, I don't know how many there will be, and I want to try and list through them, and create several variables in the list if you will.
<#list 1..10 as x>
<#-- the next line doesn't work, but what i'm trying to fix -->
<#assign .vars['VAR'+x?string] = rand(100) />
</#list>
But I can list them back out that way.
<#list 1..10 as x>
${.vars['VAR'+x?string]}
</#list>
The documentation for assign, says:
name: name of the variable. It is not expression. However, it can be
written as a string literal, which is useful if the variable name
contains reserved characters, for example <#assign "foo-bar" = 1>.
Note that this string literal does not expand interpolations (as
"${foo}").
Is there no way around this? Am I trying to do the impossible? Is there some way I can insert a derived name into the .vars... Hash is it?
A little more research that was close, but didn't get me there:
This prevoius question gives how to READ the derived variable, but I need to WRITE/CREATE the derived variable.
FreeMarker get variable value by concatenating another variable value
This prevoius question shows that I can use a string to assign a variable and re-iterates what we saw in the first link.
Variable name in Freemarker Template Language
As FreeMarker can't assign to elements of collections (but you can ?map(it -> ...) a collection to another), the only way is via ?interpret:
<#list 1..10 as x>
<#-- the next line doesn't work, but what i'm trying to fix -->
<#'<#assign VAR${x?c} = rand(100)>'?interpret />
</#list>
I wonder why do you need to assign to a dynamically named variables though, since reading dynamically named variables is also a pain, even if a lesser one.
Ultimately, I believe the correct way to phrase my solution was a sequence of hashes:
<#list 1..z_Coupon_Pet.NUM_COUPONS as x>
<#assign INSTORE_COUPON=call_coupon_from_table1() />
<#assign ONLINE_COUPON=call_coupon_from_table2() />
<#assign coupon_string_row= '{
"COUPON_NUM" : ${x},
"INSTORE" : "${INSTORE_COUPON?js_string}",
"ONLINE" : "${ONLINE_COUPON?js_string}"
}' />
<#if x==1>
<#assign coupon_hash_string = coupon_string_row />
<#else>
<#assign coupon_hash_string = coupon_hash_string + ',' + coupon_string_row />
</#if>
</#list>
</#if>
<#if coupon_hash_string?has_content>
<#assign coupon_hash=parsejson('[' + coupon_hash_string + ']') />
</#if>
We specifically avoid <#assign my_hash = my_hash + element /> because of this note in the documentation:
Note that hash concatenation is not to be used for many repeated concatenations, like for adding items to a hash inside a loop. While adding together hashes is fast and is constant time (independent of the size of the hashes added), the resulting hash is a bit slower to read than the hashes added together. Thus after tens... of additions the result can be impractically slow to read.

Freemarker, looping sequence with one object/multiple attributes

I am working on looping through one object with multiple attributes. In my scenario, I am looking for external content values.
email_address
article01
article02
article03
email#address.com
Y
Y
These values can change all the time, so we have to define them manually every instance where we use this, but I want to be able to list them in a sequence and then loop through and include them when object.attribute=Y.
The below block is purely conceptual, but referencing the attribute within the expression is where I get confused.
<#assign seq = ['article01','article02','article03']>
<#list seq as articles>
<#if base.${article}="Y">
<#include "*/${article}.htm"/>
</#if>
</#list>
In this instance, the resulting code would be:
<html><article01.html content></html>
<html><article03.html content></html>
Assuming base.articel01 would work, you can use base[article] (instead of base.${article}).

filter freemarker output by hash

<#list reports as report>
<#list report.transactionList as expense>
${expense.transactionID}^<#t>
${table[expenses.transcationID}
<#if expense.modifiedCreated?has_content>
${expense.modifiedCreated}^<#t>
<#else>
${expense.created}^<#t>
</#if>
In the above code I have a hash table called table and I want to use expense.transactionID as the key to then load the table's value like in the above code.
when I run it, the second item instead of a value is just a blank spot.
figured it out. {table[expenses.transcationID} needs to cast the category I am using as the key into a string. so the answer is: {table[expenses.transcationID?string}

Freemarker assign value to variable

I'm having trouble while trying to assign value to a variable using Freemarker.
<#if size??>
<#assign num=size?number>
<#if (num>0)>
<#list 0..num-1 as i>
<#if .vars['abc'+i?c] = "test">
<#assign .vars['abc'+i?c] = .vars['abc'+i?c]?replace("test","Test")>
</#if>
</#list>
</#if>
This is the error message: Encountered ".", but was expecting one of:
STRING_LITERAL
RAW_STRING
ID
Can anyone help me with this?
Thank you.
You can only write top-level variables in a FreeMarker template. Also you can't assign to a variable with dynamically constructed name, except with an ?interpret hack: <#"<#assign abc${i?c} = abc${i?c}?reaplce('test', "Test")>"?interpret />. Obviously that's horrid... BTW, what's the use case here? Why do you need to assign to dynamically constructed variable names?

Freemarker nested macros

How can I call nested macros as such?
<#replaceA-sToB-s>
<#replaceB-sToC-s Text/>
</#replaceA-sToB-s>
replaceB-sToC-s simply replaces any "B" with "C"
replaceA-sToB-s simply replaces any "A" with "B"
If you want to pass the result of replaceB-sToC-s macro to the replaceA-sToB-s then you have to use something like this:
<#assign str><#replaceB-sToC-s "abc" /></#assign>
<#replaceA-sToB-s str />
Like this:
<#macro replaceAsToBs>
<#local captured><#nested></#local>
${captured?replace('a', 'b')}<#t>
</#macro>
<#macro replaceBsToCs text>
${text?replace('b', 'c')}<#t>
</#macro>
(The #t-s are only there to remove the extra whitespace around the ${...} parts.) And then you call it like:
<#replaceAsToBs>
<#replaceBsToCs "abcd"/>
</#replaceAsToBs>

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