Include a file

From Rosetta Code
Include a file
You are encouraged to solve this task according to the task description, using any language you may know.

Demonstrate the language's ability to include source code from other files.

360 Assembly

The COPY instruction includes source statements from the SYSLIB library.

         COPY  member


For files containing only events (definitions and similar; no top-level function calls) which are admissible (note the lack of file extension):

(include-book "filename")

For all other files:

(ld "filename.lisp")


Some remarks are necessary here. Ada does not define how the source code is stored in files. The language rather talks about compilation units. A compilation unit "imports" another compilation unit by using context clauses - these have the syntax "with CU1, CU2, ...;". All compilers I know of require in their standard mode exactly one compilation unit per file; also file naming conventions vary. However GNAT e.g. has a mode that can deal with files holding several compilation units and any file name conventions.

with Ada.Text_IO, Another_Package; use Ada.Text_IO;    
-- the with-clause tells the compiler to include the Text_IO package from the Ada standard
-- and Another_Package. Subprograms from these packages may be called as follows:
-- Ada.Text_IO.Put_Line("some text");
-- Another_Package.Do_Something("some text");
-- The use-clause allows the program author to write a subprogram call shortly as
-- Put_Line("some text");


The formal definition of Algol68 make numerous references to the standard prelude and postlude.

At the time the language was formally defined it was typical for code to be stored on decks of punched cards (or paper tape). Possibly because storing code on disk (or drum) was expensive. Similarly card decks can be read sequentially from just one card reader. It appears the Algol68 "standard" assumed all cards could be simply stacked before and after the actual source code, hence the references "prelude" and "postlude" in the formal standard.


In the simplest case a file can be included as follows:

PR read "file.a68" PR

But in the Algol68 formal reports - it appears - the intention was to have a more structure approach.

Works with: ALGOL 68 version Revision 1 - one extension to language used - PRAGMA READ - a non standard feature similar to C's #include directive.
Works with: ALGOL 68G version Any - tested with release algol68g-2.7.
File: prelude/test.a68
# -*- coding: utf-8 -*- #
# Exception setup code: #
on value error(stand out, (REF FILE f)BOOL: GOTO value error not mended);
# Block setup code: #
printf(($"Prelude test:"l$))
File: postlude/test.a68
# -*- coding: utf-8 -*- #
# Block teardown code: #
printf(($"Postlude test."l$))
# Exception code: #
value error not mended: SKIP
File: test/include.a68
#!/usr/bin/a68g --script #
# -*- coding: utf-8 -*- #
PR read "prelude/test.a68" PR;
printf($4x"Hello, world!"l$);
PR read "postlude/test.a68" PR
Prelude test:
    Hello, world!
Postlude test.

Other implementations: e.g. ALGOL 68RS and ALGOL 68G
Note that actual source code inclusion with parsing can be avoided because of a more generalised separate compilation method storing declaration specifications in a data dictionary. Different to #include found in C where the include file needs to be parsed for each source file that includes it.


This British implementation of the language has various ways to include it's own source code and and integrate with code compiled from other languages.

Works with: ELLA ALGOL 68 version Any (with appropriate job cards) - tested with release 1.8-8d.

In order to support a top-down programming style ALGOL 68RS provided the here and context facilities.

A program could be written with parts to be filled in later marked by a here tag followed by a keeplist of declarations to be made available.

program (pass1, pass2) compiler
   string source := ...;
   tree parsetree;
   here pass1 (source, parsetree);
   instructions insts;
   here pass2 (parsetree, insts);

The code to be executed in the context of the here tags would be written as:

program pass1 implementation
context pass1 in compiler
  ...   { code using "source" and "parsetree" }

here is similar to the ALGOL 68C environ and context is equivalent to the ALGOL 68C using.


Separate compilation in ALGOL 68C is done using the ENVIRON and USING clauses. The ENVIRON saves the complete environment at the point it appears. A separate module written starting with a USING clause is effectively inserted into the first module at the point the ENVIRON clause appears.

Example of ENVIRON clause
A file called mylib.a68:

INT dim = 3; # a constant #
INT a number := 120; # a variable #
MODE MATRIX = [dim, dim]REAL; # a type definition #
a number := ENVIRON EXAMPLE2;
print((a number))

Example of USING clause
A file called usemylib.a68:

MATRIX m2; # example only #
print((a number)); # declared in mylib.a68 #
print((2 UPB m1)); # also declared in mylib.a68 #
ENVIRON EXAMPLE3; # ENVIRONs can be nested #


AntLang is made for interactive programming, but a way to load files exists. Even if it is really primitive, i. e. file get's current environment and manipulates it.


Applesoft BASIC

Chain PROGRAM TWO to PROGRAM ONE. First create and save PROGRAM TWO. Then, create PROGRAM ONE and run it. PROGRAM ONE runs and then "includes" PROGRAM TWO which is loaded and run using the Binary program CHAIN from the DOS 3.3 System Master. Variables from PROGRAM ONE are not cleared so they can be used in PROGRAM TWO. User defined functions should be redefined in PROGRAM TWO. See "Applesoft: CHAIN and user-defined functions Issues"

20 DEF FN A(X) = X * Y
30 PRINT FN A(2)
20 Y = 6
30 DEF FN A(X) = X * Y
40 PRINT FN A(2)
50 D$ = CHR$ (4)



#Include FileOrDirName
#IncludeAgain FileOrDirName


The awk extraction and reporting language does not support the use of include files. However, it is possible to provide the name of more than one source file at the command line:

awk -f one.awk -f two.awk

The functions defined in different source files will be visible from other scripts called from the same command line:

# one.awk
# two.awk
function sayhello() {
print "Hello world"

However, it is not permissible to pass the name of additional source files through a hashbang line, so the following will will not work:

#!/usr/bin/awk -f one.awk -f two.awk
Works with: Gawk

GNU Awk has an @include which can include another awk source file at that point in the code.

@include "filename.awk"

This is a parser-level construct and so must be a literal filename, not a variable or expression. If the filename is not absolute then it's sought in an $AWKPATH list of directories. See the gawk manual for more.


This will cause the program called OTHER to be parsed as if it was contained in the source code instead of this line.




other = 42


' Include a file
INCLUDE "other.bac"
PRINT other
prompt$ bacon including.bac
Converting 'including.bac'... done, 4 lines were processed in 0.005 seconds.
Compiling 'including.bac'... cc  -c including.bac.c
cc -o including including.bac.o -lbacon -lm
Done, program 'including' ready.
prompt$ ./including


Works with: QuickBASIC

The include directive must be in a comment and that the name of the file for inclusion is enclosed in single quotes (a.k.a. apostrophes).

Note that this will not work under QBasic.


See also: BBC BASIC, Gambas, IWBASIC, PowerBASIC, PureBasic, Run BASIC, ZX Spectrum Basic

Batch File

call file2.bat


      CALL filepath$

The file is loaded into memory at run-time, executed, and then discarded. It must be in 'tokenised' (internal) .BBC format.




Machine.add(me.dir() + "/");

C / C++

In C and C++, inclusion of other files is achieved via a preprocessor. The #include preprocessor directive tells the compiler to incorporate code from the included file. This is normally used near the top of a source file and is usually used to tell the compiler to include header files for the function libraries.

/* Standard and other library header names are enclosed between chevrons */
#include <stdlib.h>
/* User/in-project header names are usually enclosed between double-quotes */
#include "myutil.h"

Although it is often conventional and idiomatic for a project to use its own headers in the style described on the second line above, it's also possible to tell most compilers using various flags (e. g. GCC and Clang accept -I) to treat an arbitrary directory as a system/library include folder, thereby allowing any contained files to be included using the angle bracket syntax.


/* The C# language specification does not give a mechanism for 'including' one source file within another,
* likely because there is no need - all code compiled within one 'assembly' (individual IDE projects
* are usually compiled to separate assemblies) can 'see' all other code within that assembly.


The inclusion of other files is achieved via a preprocessor. The #include preprocessor directive tells the compiler to incorporate code from the included file. This is normally used near the top of a source file and is usually used to tell the compiler to include header files for the function libraries.

  #include "" 


Just as in Common Lisp:

(load "path/to/file")

This would rarely be used for loading code though, since Clojure supports modularisation (like most modern languages) through namespaces and code is typically located/loaded via related abstractions. It's probably more often used to load data or used for quick-and-dirty experiments in the REPL.


In COBOL, code is included from other files by the COPY statement. The files are called copybooks, normally end with the file extension '.cpy' and may contain any valid COBOL syntax. The COPY statement takes an optional REPLACING clause allows any text within the copybook to be replaced with something else.

COPY "copy.cpy". *> The full stop is mandatory, wherever the COPY is.
COPY "another-copy.cpy" REPLACING foo BY bar
==text to replace== BY ==replacement text==.

Common Lisp

(load "path/to/file")


D has a module system, so usually there is no need of a textual inclusion of a text file:

import std.stdio;

To perform a textual inclusion:


Déjà Vu

#with the module system:
#passing a file name (only works with compiled bytecode files):
!run-file "/path/"


uses SysUtils;    // Lets you use the contents of SysUtils.pas from the current unit
{$Include Common} // Inserts the contents of Common.pas into the current unit
{$I Common} // Same as the previous line, but in a shorter form


In addition to straight inclusion, there is a filtered inclusion, in which the include file goes through a pre-processing filter.

{$INCLUDE Common} // Inserts the contents of Common.pas into the current unit
{$I Common} // Same as the previous line, but in a shorter form
{$INCLUDE_ONCE Common} // Inserts the contents of Common.pas into the current unit only if not included already
{$FILTER Common} // Inserts the contents of Common.pas into the current unit after filtering
{$F Common} // Same as the previous line, but in a shorter form

Emacs Lisp

Write this code in: file1.el

(defun sum (ls)
(apply '+ ls) )

In the directory of file1.el, we write this new code in: file2.el

(add-to-list 'load-path "./")
(load "./file1.el")
(insert (format "%d" (sum (number-sequence 1 100) )))




-include("my_header.hrl"). % Includes the file at my_header.erl


include my_header.e


USING: vocaba vocabb... ;


include matrix.fs

Other Forth systems have a smarter word, which protects against multiple inclusion. The name varies: USES, REQUIRE, NEEDS.


include ''char-literal-constant''

"The interpretation of char-literal-constant is processor dependent. An example of a possible valid interpretation is that char-literal-constant is the name of a file that contains the source text to be included." See section 3.4 Including source text of the ISO standard working draft (Fortran 2003).

Included content may itself involve further inclusions but should not start with any attempt at the continuation of a statement preceding the include line nor should there be any attempt at the line following the include being a continuation of whatever had been included. It is not considered to be a statement (and so should not have a statement label) in Fortran itself but something a Fortran compiler might recognise, however a trailing comment on that line may be accepted. The exact form (if supported at all) depends on the system and its file naming conventions, especially with regard to spaces in a file name. The file name might be completely specified, or, relative as in INCLUDE "../Fortran/Library/InOutCom.for" Further, Fortran allows text strings to be delimited by apostrophes as well as by quotes and there may be different behaviour for the two sorts, if recognised. For instance, the relative naming might be with reference to the initial file being compiled, or, with reference to the directory position of the file currently being compiled - it being the source of the current include line - as where file InOutCom.for contained an inclusion line specifying another file in the same library collection.

Different compilers behave differently, and standardisation attempts have not reached back to earlier compilers.


File to be included :

' file
Type Person
name As String
age As UInteger
Declare Operator Cast() As String
End Type
Operator Person.Cast() As String
Return "[" + + ", " + Str(This.age) + "]"
End Operator

Main file :

' FB 1.05.0 Win 64
' main.bas file
#include ""
Dim person1 As Person = "Methuselah"
person1.age = 969
Print person1
Print "Press any key to quit"
[Methuselah, 969]


Use a word with a slash at the end to import; how the file is found is based on the implementation (normally the "furinc" directory is looked at for include files).

The file is imported into a new namespace. Use the same name at the beginning and a slash, but now include something else afterward, and now means that name inside of that namespace.


FB has powerful tools to include files in a project. Its "include resources" statement allows you to specify any number of files for copying into the built application package's Contents/Resources/ directory.

include resources "SomeImage.png"
include resources "SomeMovie.mpeg"
include resources "SomeSound.aiff"
include resources "SomeIcon.icns"
include resources "Info.plist" //Custom preference file to replace FB's generic app preferences

Including C or Objective-C headers (i.e. files with the .h extension) or source files (files with the .c or .m extension) requires a different 'include' syntax:

include "HeaderName.h"  // do not use 'include resources' to include C/Objective-C headers
include "CSourceFile.c"
include "ObjectiveCImplementationFile.m"

Another special case are Objective-C .nib or .xib files. These are loaded with:

include resources "main.nib"

However, .nib files are copied to the built application's Contents/Resources/en.lproj/ directory.

Mac OS X frameworks may be specified with the 'include library' statement, which has two forms:

include library "Framework/Header.h"
include library "Framework" // optional short form, expanded internally to: include library "Framework/Framework.h"

After including a Framework, you must notify the compiler of specific functions in the Framework that your code will be using with FB's "toolbox fn" statement as shown in this example:

include library "AddressBook/AddressBookUI.h"
// tell FBtoC the functions
toolbox fn ABPickerCreate() = ABPickerRef

Special treatment for C static libraries (*.a): The include statement copies the library file to the build_temp folder; you must also place the name of the library file in the preferences 'More compiler options' field [this causes it to be linked]. The example below is for a library MyLib that exports one symbol (MyLibFunction).

include "MyLib.a"
// let the compiler know about the function
void MyLibFunction( void ); // in lieu of .h file
// let FBtoC know about the function
toolbox MyLibFunction()
MyLibFunction() // call the function

An include file can also contain executable source code. Example: Suppose we create a file "Assign.incl" which contains the following lines of text:

dim as long a, b, c

a = 3
b = 7

Now suppose we write a program like this:

include "Assign.incl"
c = a + b
print c

When we compile this program, the result will be identical to this:

dim as long a, b, c
a = 3
b = 7
c = a + b
print c

Other include cases are detailed in FB's Help Center.


In gambas, files are added to the project via the project explorer main window which is a component of the integrated development environment.


Here a file is loaded into a variable

Public Sub Form_Open()
Dim sFile As String
sFile = File.Load("FileToLoad")




load "filename.gnuplot"

This is the same as done for each file named on the command line. Special filename "-" reads from standard input.

load "-"         # read standard input

If the system has popen then piped output from another program can be loaded,

load "< myprogram"       # run myprogram, read its output
load "< echo print 123"

call is the same as load but takes parameters which are then available to the sub-script as $0 through $9

call "filename.gnuplot" 123 456 "arg3"


The inclusion of other files is achieved via a preprocessor. The #include preprocessor directive tells the compiler to incorporate code from the included file. This is normally used near the top of a source file and is usually used to tell the compiler to include header files for the function libraries.

#include ""


-- Due to Haskell's module system, textual includes are rarely needed. In
-- general, one will import a module, like so:
import SomeModule
-- For actual textual inclusion, alternate methods are available. The Glasgow
-- Haskell Compiler runs the C preprocessor on source code, so #include may be
-- used:
#include "SomeModule.hs"


Current HTML specifications do not provide an include tag, Currently, in order to include content from another file, it is necessary to include content via an iframe. However, this is not supported in some browsers and looks very untidy in other browsers:

<iframe src="foobar.html">
Sorry: Your browser cannot show the included content.</iframe>

There is an unofficial tag, but this will be ignored by most browsers:


Icon and Unicon

Include another file of source code using the preprocessor statement:
$include "filename.icn"



Further, external library or object files can be specified with the $USE statement, which is a compiler preprocessor command:

$USE "libraries\\mylib.lib"

IWBASIC also allows resources, files and data that are compiled with an application and embedded in the executable. However, resources in IWBASIC may be used only for projects, i.e., programs that have more than one source file.

Various resources are loaded as follows:


ID is either a numeric or string identifier to the resource, TYPE is a numeric or string type and it stores the info in variable. The standard Windows resource types can be specified and loaded in raw form using the following constants:



The usual approach for a file named 'myheader.ijs' would be:

require 'myheader.ijs'

However, this has "include once" semantics, and if the requirement is to include the file even if it has been included earlier you would instead use:

load 'myheader.ijs'


To include source code from another file, you simply need to create an object of that other file, or 'extend' it using inheritance. The only requirement is that the other file also exists in the same directory, so that the classpath can lead to it. Since Java is quite particular about their "Class name is the same as file name" rule, if you want to use another file called Class2 in Class1, you don't need to be told a unique filename.

Just this would be enough.

public class Class1 extends Class2
//code here

You could also consider creating an instance of Class2 within Class1, and then using the instance methods.

public class Class1
Class2 c2=new Class2();
static void main(String[] args)


Pure JavaScript in browsers with the DOM

Following example, if loaded in an HTML file, loads the jQuery library from a remote site

var s = document.createElement('script');
s.type = 'application/javascript';
// path to the desired file
s.src = '';

Most be noted that it can also request HTTP source and eval() the source

With jQuery

Library: jQuery

With AMD (require.js)

require(["jquery"], function($) { /* ... */ });

CommonJS style with node.js (or browserify)

Library: node.js
var $ = require('$');

ES6 Modules

import $ from "jquery";


Works with: jq version with "include"

jq 1.5 has two directives for including library files, "include" and "import". A library file here means one that contains jq function definitions, comments, and/or directives.

The main difference between the two types of directive is that included files are in effect textually included at the point of inclusion, whereas imported files are imported into the namespace specified by the "import" directive. The "import" directive can also be used to import data.

Here we illustrate the "include" directive on the assumption that there are two files:


include "gort";


def hello: "Klaatu barada nikto";
$ jq -n -c -f Include_a_file.jq
Klaatu barada nikto.


Julia's include function executes code from an arbitrary file:


or alternatively include_string executes code in a string as if it were a file (and can optionally accept a filename to use in error messages etcetera).

Julia also has a module system:

import MyModule

imports the content of the module MyModule.jl (which should be of the form module MyModule ... end, whose symbols can be accessed as MyModule.variable, or alternatively

using MyModule

will import the module and all of its exported symbols


The closest thing Kotlin has to an #include directive is its import directive. This doesn't import source code as such but makes available names defined in another accessible package as if such names were defined in the current file i.e. the names do not need to be fully qualified except to resolve a name clash.

Either a single name or all accessible names in a particular scope (package, class, object etc.) can be imported.

For example:

fun f() = println("f called")

We can now import and invoke this from code in the default package as follows:

// version 1.1.2
import package1.f // import f from package `package1`
fun main(args: Array<String>) {
f() // invoke f without qualification
f called


In LabVIEW, any VI can be used as a "SubVI" by changing the icon and wiring the terminals to the front panel. This cannot be explained concisely in code; instead, see the documentation.


web_response -> include('')




-- load Lingo code from file
fp = xtra("fileIO").new()
fp.openFile(_movie.path&"", 1)
code = fp.readFile()
-- create new script member, assign loaded code
m = new(#script) = "someinclude"
m.scriptText = code
-- use it instantly in the current script (i.e. the script that contained the above include code)


:- object(foo).
:- include(bar).
:- end_object.


To include a header file myheader.lua:

 require "myheader" 




For textual inclusion, analogous to the C preprocessor, use the "$include" preprocessor directive. (The preprocessor is not a separate program, however.) This is frequently useful for large project development.

$include <somefile>


$include "somefile"

It is also possible to read a file, using the "read" statement. This has rather different semantics.

read "somefile":

Mathematica / Wolfram Language


MATLAB / Octave

MATLAB and Octave look for functions in *.m and *.mex included in the "path". New functions can be included, either by storing a new function in an existing path, or by extending the existing path to a new directory. When two functions have the same name, the function found first in the path takes precedence. The later is shown here:

  % add a new directory at the end of the path
addpath(newdir,'-end'); % same as before
% add a new directory at the beginning
path(newdir,path); % same as before


/* or if source.mac is in Maxima search path (see ??file_search_maxima), simply */


IMPORT  InOut, NumConv, Strings;




To include classes, static methods etc. from other namespaces, include those namespaces with the using keyword

using System.Console;

using is for accessing code that has already been compiled into libraries. Nemerle also allows for creating partial classes (and structs), the source code of which may be split amongst several files as long as the class is marked as partial in each place that part of it is defined. An interesting feature of partial classes in Nemerle is that some parts of partial classes may be written in C# while others are written in Nemerle.

public partial class Foo : Bar // all parts of a partial class must have same access modifier;
{ // the class that a partial class inherits from only needs to
... // be specified in one location


;; local file
(load "file.lsp")
;; URLs (both http:// and file:// URLs are supported)
(load "")


After import someModule an exported symbol x can be accessed as x and as someModule.x.

import someModule
import strutils except parseInt
import strutils as su, sequtils as qu # su.x works
import lib.pure.strutils, lib/pure/os, "lib/pure/times" # still strutils.x

OASYS Assembler

Use an equal sign at the beginning of a line to include a file:


In script mode and in the interactive loop (the toplevel) we can use:

#use ""

In compile mode (compiled to bytecode or compiled to native code) we can use:

include Name_of_a_module


In order to load a file with name filename :

"filename" load

In order to load a package with name pack :

import: pack


ooRexx has a package system and no ability for textual inclusion of other text files. Importing of other packages is done via the ::requires directive.

   ::requires "regex.cls"


Curly braces indicate that a file should be included. The file is searched across all PROPATH directory entries.


Arguments can be passed to the file being included:

{file.i SUPER}


//Include and run the file foo.scad
include <foo.scad>;
//Import modules and functions, but do not execute
use <bar.scad>;


Files can be loaded in GP with the read, or directly in gp with the metacommand \r.

PARI can use the standard C #include, but note that if using gp2c the embedded GP; commands must be in the original file.


See Delphi


Here we include the file into our main program:


do ""; # Utilize source from another file

sub sayhello {
print "Hello World!";
From documentation:
If "do" cannot read the file, it returns undef and sets $! to the error.
If "do" can read the file but cannot compile it, it returns undef and sets
an error message in $@.
If the file is successfully compiled, "do" returns the value of the last
expression evaluated.

Perl 6

Perl 6 provides a module system that is based primarily on importation of symbols rather than on inclusion of textual code:

use MyModule;

However, one can evaluate code from a file:

require 'myfile.p6';

One can even do that at compile time:

BEGIN require 'myfile.p6'

None of these are true inclusion, unless the require cheats and modifies the current input string of the parser. To get a true textual inclusion, one could define an unhygienic textual macro like this:

macro include(AST $file) { slurp $file.eval }


include arwen.ew

Phix also supports relative directory includes, for instance if you include "..\demo\arwen\arwen.ew" then anything that arwen.ew includes will be looked for in the appropriate directory.


There are different ways to do this in PHP. You can use a basic include:


You can be safe about it and make sure it's not included more than once:


You can crash the code at this point if the include fails for any reason by using require:


And you can use the require statement, with the safe _once method:



The function 'load' is used for recursively executing the contents of files.

(load "file1.l" "file2.l" "file3.l")


%include myfile;


Note that PowerBASIC has the optional modifier ONCE which is meant to insure that no matter how many times the file may be included in code, it will only be inserted by the compiler once (the first time the compiler is told to include that particular file).

Note also that #INCLUDE and $INCLUDE function identically.



A module is a set of related Windows PowerShell functionalities, grouped together as a convenient unit (usually saved in a
single directory). By defining a set of related script files, assemblies, and related resources as a module, you can
reference, load, persist, and share your code much easier than you would otherwise.

Import-Module -Name MyModule
When you dot source a script (or scriptblock), all variables and functions defined in the script (or scriptblock) will
persist in the shell when the script ends.

. .\MyFunctions.ps1




IncludeFile will include the named source file at the current place in the code.

IncludeFile "Filename"

XIncludeFile is exactly the same except it avoids including the same file several times.

XIncludeFile "Filename"

IncludeBinary will include a named file of any type at the current place in the code. IncludeBinary don't have to, but should preferably be done inside a data block.

IncludeBinary "Filename"


Python supports the use of execfile to allow code from arbitrary files to be executed from a program (without using its modules system).

import mymodule

includes the content of

Names in this module can be accessed as attributes:





Including files is usually discouraged in favor of using modules, but it is still possible:

#lang racket
(include "other-file.rkt")




include filename.ext


The REXX language does not include any directives to include source code from other files. A workaround is to use a preprocessor that take the source and the included modules and builds a temporary file containing all the necessary code, which then gets run by the interpreter.

Some variants of REXX may provide implementation specific solutions.

The REXX Compiler for CMS and TSO supports a directive to include program text before compiling the program

/*%INCLUDE member */

Including a file at time of execution

On the other hand, since REXX is a dynamic language, you can (mis)use some file IO and the INTERPRET statement to include another source file:

Works with: ARexx
/* Include a file and INTERPRET it; this code uses ARexx file IO BIFs */
say 'This is a program running.'
if Open(other,'SYS:Rexxc/otherprogram.rexx','READ') then do
say "Now we opened a file with another chunk of code. Let's read it into a variable."
do until EOF(other)
othercode=othercode || ReadLn(other) || ';'
call Close(other)
say 'Now we run it as part of our program.'
interpret othercode
say 'The usual program resumes here.'
exit 0

Note:   due to the way most REXX interpreters work, functions and jumps (SIGNALs) inside an INTERPRETED program won't work.   Neither are   labels   recognized, which would then exclude the use of those subroutines/functions.

There are also other restrictions such as multi-line statements and comments (more than one line).

Another possibility of errors is the creation of an extremely long value which may exceed the limit for a particular REXX interpreter.

Calling an external program

Usually, including a file in another is not necessary with REXX, since any script can be called as a function:


/* This is program 1 */
say 'This is program 1 writing on standard output.'
call Program2
say 'Thank you, program 1 is now ending.'
exit 0


/* This is program 2 */
say 'This is program 2 writing on standard output.'
say 'We now return to the caller.'

If a REXX interpreter finds a function call, it first looks in the current program for a function or procedure by that name, then it looks in the standard function library (so you may replace the standard functions with your own versions inside a program), then it looks for a program by the same name in the standard paths. This means that including a file in your program is usually not necessary, unless you want them to share global variables.


Works with: ILE RPG
      // fully qualified syntax:
/include library/file,member
// most sensible; file found on *libl:
/include file,member
// shortest one, the same library and file:
/include member
// and alternative:
/copy library/file,member
//... farther like "include"


Load 'file.ring'


Note that in Ruby, you don't use the file extension. Ruby will first check for a Ruby (.rb) file of the specified name and load it as a source file. If an .rb file is not found it will search for files in .so, .o, .dll or other shared-library formats and load them as Ruby extension. require will search in a series of pre-determined folders, while require_relative behaves the same way but searches in the current folder, or another specified folder.

require 'file'


You don't use the file extension. .bas is assumed.

run SomeProgram.bas",#include         ' this gives it a handle of #include
render #include ' render will RUN the program with handle #include


The compiler will include either a '' or a 'test/' (if the first one doesn't exist) file.

mod test
fn main() {

Additionally, third-party libraries (called crates in rust) can be declared thusly:

extern crate foo;
fn main() {


The Seed7 language is defined in the include file seed7_05.s7i. Therefore seed7_05.s7i must be included before other language features can be used (only comments can be used before). The first include directive (the one which includes seed7_05.s7i) is special and it must be introduced with the $ character.

$ include "seed7_05.s7i";

All following include directives don't need a $ to introduce them. The float.s7i library can be included with:

  include "float.s7i";


Include a file in the current namespace:

include 'file.sf';

Include a file as module (file must exists in SIDEF_INC as Some/

include Some::Name;
# variables are available here as: Some::Name::var_name


there is no such thing as source-file inclusion in Smalltalk. However, in a REPL or anywhere in code, source code can be loaded with:

aFilename asFilename readStream fileIn


Smalltalk fileIn: aFilename

In Smalltalk/X, which supports binary code loading, aFilename may either be sourcecode or a dll containing a precompiled class library.


Works with: SNOBOL4
Works with: Spitbol
-INCLUDE "path/to/"

Standard ML

Works with: SML/NJ
use "path/to/file";


The built-in source command does exactly inclusion of code into the currently executing scope, subject to minor requirements of being well-formed Tcl script that is sourced in the first place (and the ability to introspect via info script):

source "foobar.tcl"

Note that it is more usually considered good practice to arrange code into packages that can be loaded in with more regular semantics (including version handling, only-once semantics, integration of code written in other languages such as C, etc.)

package require foobar 1.3

In the case of packages that are implemented using Tcl code, these will actually be incorporated into the program using the source command, though this is formally an implementation detail of those packages.

UNIX Shell

With Bourne-compatible shells, the dot operator includes another file.

Works with: Bourne Shell
.    # Include the contents of 

C Shell

source myfile.csh



GNU Bash has both . and the C-Shell style source. See Bash manual on source


Ursa can read in and execute another file using the import statement, similar to Python.

import "filename.u"


Importing/including is done during compilation. For example, to compile the program called "maps.vala" with the package "gee":

valac maps.vala --pkg gee-1.0

Functions can be called then using Gee.<function> calls:

var map = new Gee.HashMap<string, int> ();

or with a using statement:

using Gee;
var map = new HashMap<string, int>();


VBScript doesn't come with an explicit include (unless you use the wsf form). Fortunately vbscript has the Execute and ExecuteGlobal commands which allow you to add code dynamically into the local (disappears when the code goes out of scope) or global namespaces. Thus, all you have to do to include code from a file is read the file into memory and ExecuteGlobal on that code. Just pass the filename to this sub and all is golden. If you want an error to occur if the file is not found then just remove the FileExists test.

Include "D:\include\pad.vbs"
Wscript.Echo lpad(12,14,"-")
Sub Include (file)
dim fso: set fso = CreateObject("Scripting.FileSystemObject")
if fso.FileExists(file) then ExecuteGlobal fso.OpenTextFile(file).ReadAll
End Sub

If you use the wsf form you can include a file by

<script id="Connections" language="VBScript" src="D:\include\ConnectionStrings.vbs"/>

x86 Assembly

Works with: FASM on Windows
include 'MyFile.INC'
Works with: nasm
%include "MyFile.INC"


include c:\cxpl\stdlib;
DateOut(0, GetDate)


include(vm.h.zkl, compiler.h.zkl, zkl.h.zkl, opcode.h.zkl);

ZX Spectrum Basic

It is possible to include the contents of another program using the merge command. However, line numbers that coincide with those of the original program shall be overwritten, so it is best to reserve a block of line numbers for merged code:

10 GO TO 9950
5000 REM We reserve line numbers 5000 to 8999 for merged code
9000 STOP: REM In case our line numbers are wrong
9950 REM Merge in our module
9960 REM Jump to the merged code. Pray it has the right line numbers!
9965 GO TO 5000