From d80cc79f572a94fd4fd83fced4bde420ac4bb77c Mon Sep 17 00:00:00 2001
From: Pavel Lutskov <pavel.lutskov@gmail.com>
Date: Mon, 20 Dec 2021 21:13:34 +0100
Subject: [PATCH] Use destructuring for arg splitting in engine ui

This make the arg handling code less awkward.
---
 rs/src/ui.rs | 58 +++++++++++++++++++++++++++++-----------------------
 1 file changed, 32 insertions(+), 26 deletions(-)

diff --git a/rs/src/ui.rs b/rs/src/ui.rs
index 2be95de..9e18937 100644
--- a/rs/src/ui.rs
+++ b/rs/src/ui.rs
@@ -97,42 +97,48 @@ impl Ui {
         }
     }
     fn get_state(&self, args: &[&str]) -> Result<String, String> {
-        if !args.is_empty() {
-            Err("get_state takes no args".to_owned())
-        } else {
+        if let [] = args {
             let result = format!("{}", self.board);
             Ok(result)
+        } else {
+            Err("get_state takes no args".to_owned())
         }
     }
     fn get_moves(&self, args: &[&str]) -> Result<String, String> {
-        if args.len() != 1 {
-            return Err("get_moves takes 1 arg".to_owned());
-        };
-        let position = board::Position::parse(args[0])
-            .map_err(|_| format!("Error parsing position {}", args[0]))?;
-        match self.board.get_legal_moves(&position) {
-            None => {
-                let error = format!("No moves possible from {}", position);
-                Err(error)
-            }
-            Some(positions) => {
-                Ok(positions.iter().map(|pos| format!("{}", pos)).collect())
+        if let [position_str] = args {
+            let position =
+                board::Position::parse(position_str).map_err(|_| {
+                    format!("Error parsing position {}", position_str)
+                })?;
+            match self.board.get_legal_moves(&position) {
+                None => {
+                    let error = format!("No moves possible from {}", position);
+                    Err(error)
+                }
+                Some(positions) => Ok(positions
+                    .iter()
+                    .map(|pos| format!("{}", pos))
+                    .collect()),
             }
+        } else {
+            Err("get_moves takes 1 arg".to_owned())
         }
     }
     fn make_move(&mut self, args: &[&str]) -> Result<String, String> {
-        if args.len() != 2 {
-            return Err("make_move takes 2 args".to_owned());
-        };
-        let source = board::Position::parse(args[0])
-            .map_err(|_| format!("Error parsing source {}", args[0]))?;
-        let target = board::Position::parse(args[1])
-            .map_err(|_| format!("Error parsing target {}", args[1]))?;
-        match self.board.make_move(&source, target) {
-            Err(()) => {
-                Err(format!("Move not possible {}-{}", args[0], args[1]))
+        if let [source_str, target_str] = args {
+            let source = board::Position::parse(source_str)
+                .map_err(|_| format!("Error parsing source {}", source_str))?;
+            let target = board::Position::parse(target_str)
+                .map_err(|_| format!("Error parsing target {}", target_str))?;
+            match self.board.make_move(&source, target) {
+                Err(()) => Err(format!(
+                    "Move not possible {}-{}",
+                    source_str, target_str
+                )),
+                Ok(()) => Ok(self.board.to_string()),
             }
-            Ok(()) => Ok(self.board.to_string()),
+        } else {
+            Err("make_move takes 2 args".to_owned())
         }
     }
     fn handle_command(&mut self, s: &str) -> Result<String, String> {