How do you make a block comment in SVG

Question

I'm trying to learn SVG for the first time but the code seems to have an issue with my block comments. I'm using:

/* This is my
 * block comment
 */

And when I run my code, I get the following error:

'return' statement outside of function
line: 116, column: 4

That so happens to be immediately before my block comment.

Answer 1

As SVG is XML, you can use XML style comments:

<!-- 
    comment 
-->

For example:

<g onclick = "setScale(1)">
    <rect id = "scale1" x = "120" y = "10" width = "30" height = "30"
        fill = "#ffc" stroke = "black"/>
    <!-- 
        this text describes middle rectangle
    -->
    <text x = "135" y = "30" text-anchor = "middle">M</text>
</g>

Or you can exclude some part of code:

<!--
     this group is disabled for testing    
<g onclick = "setScale(1)">
    <rect id = "scale1" x = "120" y = "10" width = "30" height = "30"
        fill = "#ffc" stroke = "black"/>
    <text x = "135" y = "30" text-anchor = "middle">M</text>
</g>
-->

Answer 2

You can use a xml tag as "desc".

<svg width="250" height="130" viewBox="0 0 250 130">
    <desc>Cuadrado que marca el viewport</desc>
    <rect x="0" y="0" height="130" width="250" style="stroke:#f00; fill: none; stroke-width:5;"></rect>

    <desc>line from top left corner to bottom right corner of the viewport</desc>
    <line x1="0" y1="0" x2="250" y2="130" style="stroke:#f00; stroke-width:1;"></line>
</svg>

Answer 3

An svg document is much the same as an html document as far as the DOM is concerned.

This line will break in all browsers:

svgDocument = evt.getTarget().getOwnerDocument();

And could simply be replaced by:

svgDocument = document;

Actually there's no real need to create a variable svgDocument since document is always defined and referring to the current document (the svg).

Please read https://jwatt.org/svg/authoring/ and in particular https://jwatt.org/svg/authoring/#asv-getters-and-setters.