RFE: StringTemplate interpolation with custom function

[Jim Laskey]

So you are looking for a different feature - escape sequence suppression. I think that can be simply addressed independently. 

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> On Oct 26, 2023, at 5:25 PM, Rob Spoor <openjdk at icemanx.nl> wrote:
> 
> Because if you URL encode the entire interpolated string the : and / inside the URL will also be encoded (to %3A and %2F respectively).
> 
> Likewise, the CSV escaping will escape all of the double quotes incorrectly.
> 
> 
>> On 26/10/2023 22:05, Jim Laskey wrote:
>> I think I’m missing something. Why wouldn’t you just;
>> import java.lang.StringTemplate.Processor;
>> Processor<URL, RuntimeException> urlEncode = template -> URLEncoder.encode(template.interpolate(), UTF_8));
>> Processor<String, RuntimeException> CSV = template -> StringEscapeUtils.escapeCsv<https://commons.apache.org/proper/commons-lang/apidocs/src-html/org/apache/commons/lang3/StringEscapeUtils.html#line.768>(template.interpolate());
>> On Oct 26, 2023, at 4:47 PM, Rob Spoor <openjdk at icemanx.nl> wrote:
>> I've been reading up on string templates, and I think it's a very cool feature. However, writing a custom processor can be a lot of copy-paste work if you want STR but with some extra translation applied. For instance, if I'd want to have a URL encoding processor I would have to write everything from scratch.
>> I think it would be useful to overload interpolate (both static and non-static) with a custom Function<Object, String> as additional arguments. This would work like STR if that provided String::valueOf as function.
>> With this method, creating a URL encoding processor would be as simple as this:
>>    var urlEncode = template -> template.interpolate(o ->
>>            URLEncoder.encode(String.valueOf(o), UTF_8));
>>    var url = urlEncode."https://host/path/\{id}?param=\{value\}";
>> Likewise, a processor backed by Apache Commons Text's StringEscapeUtils would now be just as simple:
>>    var CSV = template -> template.interpolate(o ->
>>            StringEscapeUtils.ESCAPE_CSV.translate(String.valueOf(o));
>>    var csv = CSV."""
>>            Header1, Header2, Header3
>>            "\{value1}", "\{value2}", "\{value3}"
>>            """;
>> If the JVM allows it, the existing interpolate method can even delegate to the new overload providing String::valueOf.
>