Thymeleaf loop error when using its index

I’m trying to iterate an string in Thymeleaf, letter by letter:

<div th:each="i: ${#numbers.sequence(0, #strings.length(name))}">
    <p th:text="${name.charAt(i)}"></p>
</div>

This is giving me an error:

Caused by: org.attoparser.ParseException: Exception evaluating
SpringEL expression: "name.charAt(i)" (template: "name-list" – line 8,
col 16) at
org.attoparser.MarkupParser.parseDocument(MarkupParser.java:393) at
org.attoparser.MarkupParser.parse(MarkupParser.java:257) at
org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:230)
… 48 more

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If I do

<div th:each="i: ${#numbers.sequence(0, #strings.length(name))}">
    <p th:text="${name.charAt(2)}"></p>
</div>

Thymeleaf does not complain and gives me what I want. Thank you.

>Solution :

Your index is going out of bounds. Subtract one from the length of the string for the endpoint of the sequence (which is inclusive).

<div th:each="i: ${#numbers.sequence(0, #strings.length(name) - 1)}">

You can directly use [i] to access the character by index rather than charAt also.

<p th:text="${name[i]}"/>

To avoid working with indexes, you can loop over the characters of the string (obtainable by calling toCharArray()).

<div th:each="c: ${name.toCharArray()}">
    <p th:text="${c}"/>
</div>