Improving slicing for #10

`Table` can now be transmuted to `TableSlice`

1 files changed, 24 insertions, 19 deletions

diff --git a/src/lib.rs b/src/lib.rs
index c2dc6d1..240d1cc 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -7,6 +7,7 @@ use std::io::{Write, Error};
 use std::fmt;

 use std::iter::{FromIterator, IntoIterator};

 use std::ops::{Index, IndexMut};

+use std::mem::transmute;

 

 use term::{Terminal, stdout};

 

@@ -23,8 +24,8 @@ use utils::StringWriter;
 /// A Struct representing a printable table

 #[derive(Clone, Debug)]

 pub struct Table {

-	format: TableFormat,

-	titles: Option<Row>,

+	format: Box<TableFormat>,

+	titles: Box<Option<Row>>,

 	rows: Vec<Row>

 }

 

@@ -139,19 +140,27 @@ impl Table {
 	pub fn init(rows: Vec<Row>) -> Table {

 		return Table {

 			rows: rows,

-			titles: None,

-			format: FORMAT_DEFAULT

+			titles: Box::new(None),

+			format: Box::new(FORMAT_DEFAULT)

 		};

 	}

 

+	pub fn as_slice<'a>(&'a self) -> &'a TableSlice<'a> {

+		unsafe {

+			let s: &mut Table = &mut *((self as *const Table) as *mut Table);

+			s.rows.shrink_to_fit();

+			return transmute(self);

+		}

+	}

+

 	/// Change the table format. Eg : Separators

 	pub fn set_format(&mut self, format: TableFormat) {

-		self.format = format;

+		*self.format = format;

 	}

 

 	/// Compute and return the number of column

 	pub fn get_column_num(&self) -> usize {

-		return self.slice(..).get_column_num();

+		return self.as_slice().get_column_num();

 	}

 

 	/// Get the number of rows

@@ -161,12 +170,12 @@ impl Table {
 

 	/// Set the optional title lines

 	pub fn set_titles(&mut self, titles: Row) {

-		self.titles = Some(titles);

+		*self.titles = Some(titles);

 	}

 

 	/// Unset the title line

 	pub fn unset_titles(&mut self) {

-		self.titles = None;

+		*self.titles = None;

 	}

 

 	/// Get a mutable reference to a row

@@ -220,13 +229,13 @@ impl Table {
 	/// **[DEPRECATED]** Get the width of the column at position `col_idx`.

 	/// Return 0 if the column does not exists;

 	pub fn get_column_width(&self, col_idx: usize) -> usize {

-		return self.slice(..).get_column_width(col_idx);

+		return self.as_slice().get_column_width(col_idx);

 	}

 

 	/// **[DEPRECATED]** Get the width of all columns, and return a slice

 	/// with the result for each column

 	pub fn get_all_column_width(&self) -> Vec<usize> {

-		return self.slice(..).get_all_column_width();

+		return self.as_slice().get_all_column_width();

 	}

 

 	/// Return an iterator over the immutable cells of the column specified by `column`

@@ -241,19 +250,19 @@ impl Table {
 

 	/// Print the table to `out`

 	pub fn print<T: Write+?Sized>(&self, out: &mut T) -> Result<(), Error> {

-		return self.slice(..).print(out);

+		return self.as_slice().print(out);

 	}

 

 	/// Print the table to terminal `out`, applying styles when needed

 	pub fn print_term<T: Terminal+?Sized>(&self, out: &mut T) -> Result<(), Error> {

-		return self.slice(..).print_term(out);

+		return self.as_slice().print_term(out);

 	}

 

 	/// Print the table to standard output

 	/// # Panic

 	/// Panic if writing to standard output fails

 	pub fn printstd(&self) {

-		self.slice(..).printstd();

+		self.as_slice().printstd();

 	}

 }

 

@@ -332,14 +341,10 @@ pub trait Slice<'a, E> {
 	fn slice(&'a self, arg: E) -> Self::Output;

 }

 

-impl <'a, E> Slice<'a, E> for Table where Vec<Row>: Index<E, Output=[Row]> {

+impl <'a, E> Slice<'a, E> for Table where [Row]: Index<E, Output=[Row]> {

 	type Output = TableSlice<'a>;

 	fn slice(&'a self, arg: E) -> Self::Output {

-		return TableSlice {

-			format: &self.format,

-			titles: &self.titles,

-			rows: &self.rows[arg]

-		}

+		return self.as_slice().slice(arg);

 	}

 }