调试树

此库允许您逐个元素构建树，并以漂亮的字符串形式输出。

树可以轻松输出到 String、stdout 或文件。

这对于从嵌套和递归函数中生成干净的输出尤其方便。

• 递归 Fibonacci 示例
• 概述
• 更多示例
  • 多个标记树
  • 嵌套函数
  • 恐慌
  • 无宏

递归 Fibonacci 示例

在 factors() 函数的开始处使用 add_branch!() 宏，您可以以最小的努力生成整个调用树。

use debug_tree::*;

fn factors(x: usize) {
    add_branch!("{}", x); // <~ THE MAGIC LINE
    for i in 1..x {
        if x % i == 0 {
            factors(i);
        }
    }
}

fn main() {
    // output to file at the end of this block
    defer_write!("examples/out/fibonacci.txt");
    add_branch!("A Fibonacci Tree");
    factors(6);
    add_leaf!("That's All Folks!");
}

A Fibonacci Tree
├╼ 6
│ ├╼ 1
│ ├╼ 2
│ │ └╼ 1
│ └╼ 3
│   └╼ 1
└╼ That's All Folks!

概述

• 添加分支

  • add_branch!("Hello, {}", "World")
  • 分支将在当前块的末尾退出

• 添加叶子节点

  • add_leaf!("I am a {}", "leaf")
  • 已添加到当前作用域的分支

• 在块结束时打印树，或将它写入文件

  • defer_print!()
  • defer_write!("filename.txt")
  • 这些调用之后树将为空
  • 为防止清除，请使用 defer_peek_print! 和 defer_peek_write!

• 使用命名树处理多个树

  • add_branch_to!("A", "I'm a branch on tree 'A'")
  • add_leaf_to!("A", "I'm a leaf on tree 'A'")
  • defer_print!("A")
  • defer_write!("A", "filename.txt")

• 获取命名树

  • tree("TREE_NAME")

• 从树中检索漂亮的字符串

  • tree("TREE_NAME").string()

• 跨线程使用

  • default_tree() 是每个线程本地的
  • 命名树在线程间共享

更多示例

多个标记树

如果您需要多个独立的树，可以使用名称标签。

use debug_tree::*;

fn populate(tree_name: &str, n_children: usize) {
    add_branch_to!(tree_name, "{} TREE", tree_name);
    for _ in 0..n_children {
        populate(tree_name, n_children / 2);
    }
}
fn main() {
    // Override tree config (just for "B")
    let b_tree = tree("B");
    b_tree.set_config_override(
        TreeConfig::new()
            .indent(4)
            .symbols(TreeSymbols::with_rounded().leaf("> ")),
    );
    defer_write!(b_tree, "examples/out/multiple_trees_B.txt");
    defer_write!("A", "examples/out/multiple_trees_A.txt");

    populate("A", 2);
    populate("B", 3);
}

A TREE
├╼ A TREE
│ └╼ A TREE
└╼ A TREE
  └╼ A TREE

B TREE
├──> B TREE
│   ╰──> B TREE
├──> B TREE
│   ╰──> B TREE
╰──> B TREE
    ╰──> B TREE

嵌套函数

分支也使得嵌套函数调用更容易追踪。

use debug_tree::*;
fn a() {
    add_branch!("a");
    b();
    c();
}
fn b() {
    add_branch!("b");
    c();
}
fn c() {
    add_branch!("c");
    add_leaf!("Nothing to see here");
}

fn main() {
    defer_write!("examples/out/nested.txt");
    a();
}

a
├╼ b
│ └╼ c
│   └╼ Nothing to see here
└╼ c
  └╼ Nothing to see here

行断

多行字符串中的换行将被自动缩进。

use debug_tree::*;
fn main() {
    // output to file at the end of this block
    defer_write!("examples/out/multi_line.txt");
    add_branch!("1");
    add_leaf!("1.1\nAnother line...\n... and one more line");
    add_leaf!("1.2");
}

1
├╼ 1.1
│  Another line...
│  ... and one more line
└╼ 1.2

恐慌

即使发生恐慌，树也不会丢失！defer_ 函数被引入，以便在发生 panic! 或早期返回时将树打印或写入文件。

use debug_tree::*;

fn i_will_panic() {
    add_branch!("Here are my last words");
    add_leaf!("Stay calm, and try not to panic");
    panic!("I told you so...")
}

fn main() {
    // output to file at the end of this block
    defer_write!("examples/out/panic.txt");
    // print at the end of this block
    {
        add_branch!("By using the 'defer_' functions");
        add_branch!("Output will still be generated");
        add_branch!("Otherwise you might lose your valuable tree!");
    }
    add_branch!("Now for something crazy...");
    i_will_panic();
}

By using the 'defer_' functions
└╼ Output will still be generated
  └╼ Otherwise you might lose your valuable tree!
Now for something crazy...
└╼ Here are my last words
  └╼ Stay calm, and try not to panic

无宏

如果您不喜欢使用宏，您可以手动构造 TreeBuilder。

use debug_tree::TreeBuilder;

fn main() {
    // Make a new tree.
    let tree = TreeBuilder::new();

    // Add a scoped branch. The next item added will belong to the branch.
    let mut branch = tree.add_branch("1 Branch");

    // Add a leaf to the current branch
    tree.add_leaf("1.1 Child");

    // Leave scope early
    branch.release();
    tree.add_leaf("2 Sibling");
    // output to file
    tree.write("examples/out/no_macros.txt").ok(); // Write and flush.
}

1 Branch
└╼ 1.1 Child
2 Sibling