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Re:PEP 750 – Template Strings (t-strings) have been accepted by zahlman on Thursday April 10, 2025 @10:18PM (#43649876)
In case there was confusion: Python's f-string functionality in particular is specific to string literals. The f prefix doesn't create a different data type; instead, the contents of the literal are parsed at compile time and the entire thing is rewritten into equivalent string concatenation code (although IIRC it uses dedicated bytecodes, in at least some versions).

The t-string proposal involves using new data types to abstract the concatenation and formatting process, but it's still a compile-time process - and the parts between the braces still involve code that executes first - and there's still no separate type for the overall t-string literal, and no way to end up eval'ing code from user-supplied data except by explicitly requesting to do so.

Re:PEP 750 – Template Strings (t-strings) have been accepted by the_clarence on Thursday April 10, 2025 @11:40PM (#43650297)
There is no compile time in python
Re:PEP 750 – Template Strings (t-strings) have been accepted by zahlman on Thursday April 10, 2025 @11:54PM (#43650365)
Yes, there is.

Python source code is translated into bytecode for a VM just like in Java or C#, and by default it's cached in .pyc files. It's only different in that you can ask to execute a source code file and the compilation happens automatically before the bytecode-interpretation.

`SyntaxError` is fundamentally different from other exceptions because it can occur during compilation, and only occurs at run-time if explicitly raised (or via explicit invocation of another code compilation, such as with `exec`/`eval`, or importing a module). This is also why you can't catch a `SyntaxError` caused by the invalid syntax of your own code, but only from such an explicit `raise` or a request to compile a source code string (see https://stackoverflow.com/questions/1856408 ).

Re:PEP 750 – Template Strings (t-strings) have been accepted by pansa2 on Thursday April 10, 2025 @11:43PM (#43650315)
Yes there is, when it compiles source code to bytecode.