luallaby 0.1.0

**Work in progress** A pure-Rust Lua interpreter/compiler
Documentation 
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use crate::ast::Local;
use crate::compiler::Compiler;
use crate::error::Result;
use crate::vm::OpCode;

impl Compiler {
    pub(super) fn compile_local(&mut self, local: Local) -> Result<()> {
        let mut end = Vec::new();
        let mut to_free = Vec::new();

        let exp_regs: Vec<usize> = local
            .exps
            .into_iter()
            .map(|exp| self.compile_exp(exp))
            .collect::<Result<_>>()?;

        for (ind, (name, attr, pos)) in local.vars.into_iter().enumerate() {
            let dst_loc = self.declare_local(name, attr, pos);

            if !exp_regs.is_empty() {
                let src_reg = if ind + 1 < exp_regs.len() {
                    exp_regs[ind]
                } else {
                    let dst_reg = self.scopes.reg_reserve();
                    self.code.emit(
                        OpCode::MovMult {
                            src_reg: *exp_regs.last().unwrap(),
                            ind: ind + 1 - exp_regs.len(),
                            dst_reg,
                        },
                        pos,
                    );
                    to_free.push(dst_reg);
                    dst_reg
                };
                end.push(OpCode::LocalSet { src_reg, dst_loc });
            }
        }

        self.code.emit_all(end, self.code.get_pos_last());
        for reg in exp_regs {
            self.scopes.reg_free(reg);
        }
        for reg in to_free {
            self.scopes.reg_free(reg);
        }

        Ok(())
    }
}