Merge branch 'master' into units

Cargo.lock

@@ -138,7 +138,7 @@ dependencies = [
 
 [[package]]
 name = "kalk"
-version = "0.1.9"
+version = "0.1.10"
 dependencies = [
  "phf",
  "regex",
@@ -148,7 +148,7 @@ dependencies = [
 
 [[package]]
 name = "kalk_cli"
-version = "0.1.8"
+version = "0.1.9"
 dependencies = [
  "ansi_term",
  "kalk",

README.md

@@ -5,7 +5,8 @@
 ![Build status](https://img.shields.io/travis/PaddiM8/kalk/master?label=build%20%26%20test)
 
 
-Kalk is a calculator (both program and library) that supports user-defined variables and functions.
+Kalk is a calculator (both program and library) that supports user-defined variables and functions.  
+[Project kanban board (Kolan)](https://kolan.smrk.me/Board/4RAdMjLDz)
 
 ![](example.png)
 

kalk/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "kalk"
-version = "0.1.9"
+version = "0.1.10"
 authors = ["PaddiM8"]
 edition = "2018"
 readme = "README.md"

kalk_cli/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "kalk_cli"
-version = "0.1.8"
+version = "0.1.9"
 authors = ["PaddiM8"]
 edition = "2018"
 readme = "../README.md"
@@ -15,7 +15,7 @@ path = "src/main.rs"
 name = "kalk"
 
 [dependencies]
-kalk = { path = "../kalk", version = "^0.1.9" }
+kalk = { path = "../kalk", version = "^0.1.10" }
 rustyline = "6.1.2"
 ansi_term = "0.12"
 regex = "1"

kalk_cli/src/main.rs

@@ -21,22 +21,37 @@ fn main() {
             break;
         };
 
-        if arg == "-i" {
-            let file_name = &args.next().expect("Expected input file."); // The next argument will be the file name.
-            let mut file_content = String::new();
-            File::open(&file_name)
-                .expect("Couldn't find file.")
-                .read_to_string(&mut file_content)
-                .expect("Failed to read input file.");
+        match arg.as_ref() {
+            "-h" | "--help" => {
+                // The indentation... Will have to do something more scalable in the future.
+                println!(
+                    "
+-= kalk help =-\n
+kalk [OPTIONS] [INPUT]
+-h, --help : show this
+-i         : load a file with predefined functions/variables
+                "
+                );
+                return;
+            }
+            "-i" => {
+                let file_name = &args.next().expect("Expected input file."); // The next argument will be the file name.
+                let mut file_content = String::new();
+                File::open(&file_name)
+                    .expect("Couldn't find file.")
+                    .read_to_string(&mut file_content)
+                    .expect("Failed to read input file.");
 
-            // Parse the input file content, resulting in the symbol table being filled out.
-            // Output is not needed here.
-            parser::eval(&mut parser_context, &file_content, 53)
-                .expect("Failed to parse input file.");
-        } else {
-            // Main argument. This is expected to be a maths expression.
-            // After the loop is finished, this will be parsed and outputted.
-            expr_input = Some(arg);
+                // Parse the input file content, resulting in the symbol table being filled out.
+                // Output is not needed here.
+                parser::eval(&mut parser_context, &file_content, 53)
+                    .expect("Failed to parse input file.");
+            }
+            _ => {
+                // Main argument. This is expected to be a maths expression.
+                // After the loop is finished, this will be parsed and outputted.
+                expr_input = Some(arg);
+            }
         }
     }
 

kalk_cli/src/output.rs

@@ -16,7 +16,11 @@ pub fn eval(parser: &mut parser::Context, input: &str) {
 
                 let num = if exp <= 0 {
                     // 0 < x < 1
-                    format!("0.{}{}", "0".repeat(exp.abs() as usize), digits)
+                    round(
+                        format!("0.{}{}", "0".repeat(exp.abs() as usize), digits)
+                            .trim_end_matches('0'),
+                    )
+                    .to_string()
                 } else if use_sci_notation || result.fract() != 0 {
                     // Insert the comma if there are supposed to be decimals.
                     let mut chars: Vec<char> = digits
@@ -25,7 +29,7 @@ pub fn eval(parser: &mut parser::Context, input: &str) {
                         .chars()
                         .collect();
                     chars.insert(comma_pos, '.');
-                    chars.into_iter().collect::<String>()
+                    round(&chars.into_iter().collect::<String>()).to_string()
                 } else {
                     // Regular number
                     digits[..(exp as usize)].to_string()
@@ -47,6 +51,39 @@ pub fn print_err(msg: &str) {
     println!("{}", Red.paint(msg));
 }
 
+fn round(value: &str) -> String {
+    let mut value_iter = value.chars().into_iter().rev().skip(1);
+    let last_char = value_iter.next().unwrap();
+    let mut last_char_count = 1;
+
+    // Find out how many repeating trailing (equal) characters there are
+    for c in value_iter {
+        if c == last_char {
+            last_char_count += 1;
+        } else {
+            break;
+        }
+    }
+
+    // Don't round if there aren't that many
+    if last_char_count < 5 {
+        return value.to_string();
+    }
+
+    // Remove zeroes.
+    // If it's nines, round it up.
+    // Otherwise, only show 3 of them and then three dots:
+    match last_char {
+        '0' => value[..value.len() - last_char_count - 1].to_string(),
+        '9' => value.parse::<f32>().unwrap().ceil().to_string(),
+        _ => format!(
+            "{}{}...",
+            &value[..value.len() - last_char_count - 1],
+            last_char.to_string().repeat(3)
+        ),
+    }
+}
+
 fn print_calc_err(err: CalcError) {
     print_err(&match err {
         IncorrectAmountOfArguments(expected, func, got) => format!(