finds run in path

src/arg/mod.rs

@@ -1,6 +1,9 @@
 use std::{
     error,
     fmt,
+    path::{
+	PathBuf,
+    },
 };
 
 #[cfg(feature = "broken-pipe")]
@@ -14,6 +17,8 @@ pub struct ProcessArgs
 {
     pub name: String,
     pub args: Vec<String>,
+    
+    name_real: Option<PathBuf>, //get => `.name_path()`
 }
 
 mod proc_args;
@@ -74,17 +79,17 @@ impl Operation
 	&self.outputs
     }
 
-    pub fn validate(&self) -> Result<(), String>
+    pub fn validate(&mut self) -> Result<(), String>
     {
 	if !self.output_to_tty && self.outputs.len()<1 {
 	    return Err("Need at least one output.".to_owned());
 	}
 
-	self.input.verify().or_else(|err| Err(format!("bad input <{}>: {}", &self.input, err)))?;
+	self.input.name_real = Some(self.input.verify().or_else(|err| Err(format!("bad input <{}>: {}", &self.input, err)))?);
 	
-	for x in self.outputs.iter()
+	for x in self.outputs.iter_mut()
 	{
-	    x.verify().or_else(|err| Err(format!("bad output <{}>: {}", &x, err)))?;
+	    x.name_real = Some(x.verify().or_else(|err| Err(format!("bad output <{}>: {}", &x, err)))?);
 	}
 	
 	Ok(())

src/arg/proc_args.rs

@@ -1,4 +1,7 @@
 use super::*;
+use std::{
+    path::{Path,PathBuf,},
+};
 
 impl ProcessArgs
 {
@@ -23,14 +26,97 @@ impl ProcessArgs
 	Ok(Self{
 	    name,
 	    args,
+	    name_real: None,
 	})
     }
 
-    pub fn verify(&self) -> Result<(), &'static str>
+    pub fn name_path(&self) -> Result<&Path, &'static str>
     {
-	//TODO: Check file path of executable
-	Ok(())
+	if let Some(buf) = &self.name_real {
+	    Ok(buf.as_ref())
+	} else {
+	    Err("No name_path specified, have you called `verify()`?")
+	}
+    }
+
+    pub fn verify(&self) -> Result<PathBuf, &'static str>
+    {
+	if let Ok(spath) = std::env::var("PATH") {
+	    if let Some(path) = find_somewhere(&self.name, spath.split(':')) {
+		Ok(path)
+	    } else {
+		Err("File not found")
+	    }
+	} else if Path::new(&self.name).exists() {
+	     Ok(Path::new(&self.name).to_owned())
+	} else {
+	    Err("File not found and $PATH not found.")
+	}
     }
 }
 
-//TODO: impl fmt::Display for ProcessArgs
+fn find_somewhere<T,U,V>(name: T, places: U) -> Option<PathBuf>
+where T: AsRef<str>,
+      U: Iterator<Item=V>,
+      V: AsRef<str>
+{
+    let name = name.as_ref();
+
+    let pbuf = Path::new(&name);
+    if pbuf.exists() {
+	return Some(pbuf.to_owned())
+    }
+    
+    for place in places
+    {
+	let place = place.as_ref();
+
+	let pbuf = Path::new(&place).join(&name);
+	if pbuf.exists() {
+	    return Some(pbuf);   
+	}
+    }
+
+    None
+}
+
+fn escape<T>(s: &T) -> String
+where T: AsRef<str> + ?Sized
+{
+    let s = s.as_ref();
+    let mut o = String::with_capacity(s.len());
+
+    for c in s.chars() {
+	match c {
+	    '\\' => {
+		o.push('\\');
+		o.push('\\');
+	    },
+	    '\'' => {
+		o.push('\\');
+		o.push('\'');
+	    },
+	    other => o.push(other),
+	};
+    }
+
+    o
+}
+
+use std::fmt;
+impl fmt::Display for ProcessArgs
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
+    {
+	write!(f, "{} ", self.name)?;
+	let len = self.args.len();
+	for (i,x) in (0..len).zip(self.args.iter()) {
+	    write!(f, "{}", &x)?;
+	    if i < len-1 {
+		write!(f, " ")?;
+	    }
+	}
+
+	Ok(())
+    }
+}

src/main.rs

@@ -10,7 +10,8 @@ mod arg;
 fn main() -> Result<(), Box<dyn Error>> {
     let op = arg::parse()?;
 
-    //println!("{:?}", op); yay!
+    //TODO: Open input
+    println!("{:?}", op);
     
     Ok(())
 }