Here’s a complete “Ideal 2”. It’s not an f-string—it doesn’t even use f-strings—but it does as requested. Syntax exactly as specified. No security headaches since we are not using eval(). It uses a little class and implements __str__ which is automatically called by print. To escape the limited scope of the class we use the … Read more
Only double quoted strings interpret the escape sequences \r and \n as ‘0x0D’ and ‘0x0A’ respectively, so you want: “\r\n” Single quoted strings, on the other hand, only know the escape sequences \\ and \’. So unless you concatenate the single quoted string with a line break generated elsewhere (e. g., using double quoted string … Read more
Python 3.6 will add literal string interpolation similar to Ruby’s string interpolation. Starting with that version of Python (which is scheduled to be released by the end of 2016), you will be able to include expressions in “f-strings”, e.g. name = “Spongebob Squarepants” print(f”Who lives in a Pineapple under the sea? {name}.”) Prior to 3.6, … Read more
As suggested by Josh Lee in the comment section, that kind of string interpolation was added in Python 3.6 only, see What’s New In Python 3.6 (here it’s called “PEP 498: Formatted string literals”). You, however, seems to be using Python 3.5.2, which does not support that syntax.
As per SE-0054, ImplicitlyUnwrappedOptional<T> is no longer a distinct type; there is only Optional<T> now. Declarations are still allowed to be annotated as implicitly unwrapped optionals T!, but doing so just adds a hidden attribute to inform the compiler that their value may be force unwrapped in contexts that demand their unwrapped type T; their … Read more
You can take advantage of Template Literals and use this syntax: `String text ${expression}` Template literals are enclosed by the back-tick (` `) (grave accent) instead of double or single quotes. This feature has been introduced in ES2015 (ES6). Example var a = 5; var b = 10; console.log(`Fifteen is ${a + b}.`); // “Fifteen … Read more
Since ES6, you can use template literals: const age = 3 console.log(`I’m ${age} years old!`) P.S. Note the use of backticks: “.
When you enclose a variable name in a double-quoted string it will be replaced by that variable’s value: $foo = 2 “$foo” becomes “2” If you don’t want that you have to use single quotes: $foo = 2 ‘$foo’ However, if you want to access properties, or use indexes on variables in a double-quoted string, … Read more