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Comment by HexDecOctBin | Hacker News Reader

Last time I tried Lazarus, the strangest feature that FPC was missing when compared to Delphi was being able to declare variables anywhere (as opposed to only at the top of a block). FPC is still stuck in a very C89 model of declarations for some reason, perhaps that's just what happens when ecosystems stagnate.

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That feature you mentioned was added by the Delphi team in support of closures. They way they developed it was jankey IMO, as it creates an interface behind the scenes and populate with information about the local stack.

Though I do very much appreciate C#, with its lambda functions, expression trees, and especially the tooling, Free Pascal and Lazarus exist as a happy compromise between those things and native code integration, where working with C libraries like libcairo, libxml2, libssl, libsdl, and opengl are much easier and a pleasure to work with when using Free Pascal, and conversely are more difficult to wrangle when using C# or Java.

All OP is asking for is the ability to declare variables at first use instead of at the top of a function. You don't need closures or anything that'd inhibit C compatibility for this - C itself has supported this since C99. It's fairly simple if you're willing to give up single-pass compilation, which (I think?) FPC already has.

Could probably just get the source and have an LLM vibe code that, for personal use seems fine.

I think OP is talking about inline variables (in Delphi terminology), ie writing a var or const where you use it instead of in a var or const block at the top of the method.

Anonymous methods are the ones that are implemented via an interfaced object. It is a bit odd and I wish they had chosen something more ABI-compatible with a C++ functor, since it would have made mapping between the two easier IMO.

I have a test branch of the Oxygene compiler -- no idea if we'll merge it in, we make syntax experiments regularly -- where all callables are assignment-compatible. In Delphi terms this means assigning an anon method to an event handler would work, but equally for us, lambdas, blocks, and more. The idea is somewhat C++-like in terms of std::function and std::bind but with simple syntax in that you write it and it works: if it can be called, it can be applied where any callable method-like expectation exists.

see Unleashed Pascal - a community driven fork of FPC/Lazarus:

https://unleashedpascal.org/

I hope in time it also adopts the dynamic packages work in this thread.

There is some interesting innovation going on in the Pascal community (including AI, ML, Agent frameworks etc) - it is just not very visible in the wider tech world.

Thanks, I didn't know this existed.

> There is some interesting innovation going on in the Pascal community

Links please :)

In addition to unleashed and the dynamics package in this thread, some illustrative examples:

Coding agent inside Lazarus: https://forum.lazarus.freepascal.org/index.php/topic,75061.0...

Deep learning in Pascal: https://github.com/joaopauloschuler/neural-api

AI orchestration: https://github.com/gustavoeenriquez/MakerAi/tree/fpc

AI agent framework: https://github.com/FMXExpress/PasClaw

New Object Pascal compiler: https://github.com/graemeg/blaise

A lot more can be discovered on https://forum.lazarus.freepascal.org/

have fun!

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