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StringTemplate never automatically wraps lines--you must explicitly use the wrap option on an expression to indicate that StringTemplate should wrap lines in between expression elements. StringTemplate never breaks literals, but it can break in between a literal and an expression. the line wrapping is soft in the sense that an expression that emits text starting before the right edge will spit out that element even if it goes past the right edge. In other words, StringTemplate does not break elements to enforce a hard right edge. It will not break line between element and separator to avoid having for example a comma appear at the left edge. You may specify the line width as an argument to toString() such as st.toString(72). By default, toString() does not wrap lines.
That said, if there's a newline in the literal to emit, it will wrap at the newline.
To illustrate the simplest form of line wrapping, consider a simple list of characters that you would like to wrap at, say, line width 3. Use the wrap option on the chars expression:
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