I encountered a problem while reading PHP-related tutorial books. Please forgive me for being too clumsy. Forgive me for using a capitalized book title number instead of <>, otherwise a line break will be automatically displayed.
echo "a: [".(20>9)."]《br》";
The above is a simple Boolean expression
Why should the line break symbol of "br" be written in ""? And if it is written between "and;, an error will be reported?
(
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You can
echo "a:[.(20>9)."], '<br>';