Editing Euphoria (programming language) (section)

==Examples==
Program comments start with a double hyphen <code>--</code> and go through the end of line.

The following code looks for an old item in a group of items. If found, it removes it by concatenating all the elements before it with all the elements after it. Note that the first element in a sequence has the index one [1] and that $ refers to the length (i.e., total number of elements) of the sequence.

 <span style="color:blue;">global function</span> delete_item( <span style="color:magenta;">object</span> old, <span style="color:magenta;">sequence</span> group )
     <span style="color:magenta;">integer</span> pos
             <span style="color:red;">-- Code begins --</span>
     pos = <span style="color:magenta;">find</span>( old, group )
     <span style="color:blue;">if</span> pos > 0 <span style="color:blue;">then</span>
         group = group[1 .. pos-1] & group[pos+1 .. $]
     <span style="color:blue;">end if
     return</span> group
 <span style="color:blue;">end function</span>

The following modification to the above example replaces an old item with a new item. As the variables ''old'' and ''new'' have been defined as objects, they could be ''atoms'' or ''sequences''. Type checking is not needed as the function will work with any sequence of data of any type and needs no external libraries.

 <span style="color:blue;">global function</span> replace_item( <span style="color:magenta;">object</span> old, <span style="color:magenta;">object</span> new, <span style="color:magenta;">sequence</span> group )
     <span style="color:magenta;">integer</span> pos
             <span style="color:red;">-- Code begins --</span>
     pos = <span style="color:magenta;">find</span>( old, group )
     <span style="color:blue;">if</span> pos > 0 <span style="color:blue;">then</span>
         group[pos] = new
     <span style="color:blue;">end if
     return</span> group
 <span style="color:blue;">end function</span>

Furthermore, no pointers are involved and subscripts are automatically checked. Thus the function cannot access memory out-of-bounds. There is no need to allocate or deallocate memory explicitly and no chance of a memory leak.

The line

 group = group[1 .. pos-1] & group[pos+1 .. $]

shows some of the ''sequence'' handling facilities. A ''sequence'' may contain a set of any types, and this can be sliced (to take a subset of the data in a ''sequence'') and concatenated in expressions with no need for special functions.