chore: reorg

__std/into/src/main.rs

@@ -0,0 +1,53 @@
+
+use std::convert::{
+    TryInto,
+    TryFrom,
+};
+
+type BoxError = Box<dyn std::error::Error>;
+type XResult<T> = Result<T, BoxError>;
+
+fn do_print<T>(t: T) -> XResult<()> where T: TryInto<String>, T::Error: Into<BoxError> {
+    println!("--> {}", t.try_into().map_err(Into::into)?);
+    Ok(())
+}
+
+fn do_print2<T>(t: T) where T: Into<String> {
+    println!("==> {}", t.into())
+}
+
+struct StructX {
+    name: String,
+}
+
+struct StructY {
+    name: String,
+}
+
+// auto have: TryInto<String> for StructX
+impl TryFrom<StructX> for String {
+    type Error = BoxError;
+
+    fn try_from(sx: StructX) -> XResult<Self> {
+        Ok(format!("NAME: {}", sx.name))
+    }
+}
+
+impl From<StructY> for String {
+
+    fn from(sx: StructY) -> Self {
+        format!("NAME:: {}", sx.name)
+    }
+}
+
+fn main() -> XResult<()> {
+    let x = StructX {
+        name: "hater".to_owned(),
+    };
+    do_print(x)?;
+    let y = StructY {
+        name: "hater".to_owned(),
+    };
+    do_print2(y);
+    Ok(())
+}