Using Morpho

Morpho is a command line application, like python or lua. It can be used to run scripts or programs, which are generally given the .morpho file extension, or run interactively responding to user commands.

Running a program

To run a program, simply run morpho with the name of the file,

morpho6 script.morpho

Morpho supports a number of switches:

-w : Run morpho with more than one worker thread, e.g. -w 4 runs morpho with 4 threads.

-D: Display disassembly of the program without running it. [See developer guide]

-d : Debugging mode. Morpho will stop and enter the debugger whenever a @ is encountered in the source. [See developer guide]

-p : Profile the program execution. Useful to identify performance bottlenecks. [See developer guide]

Interactive mode

To use morpho interactively, simply load the Terminal application (or equivalent on your system) and type

morpho6

Command line interface for Morpho

As shown in the figure above, you'll be greeted by a brief welcome and a prompt > inviting you to enter morpho commands. For now, try a classic:

print "Hello World"

which will display Hello World as output. More information about the morpho language is provided in the Reference section, especially chapter Language if you're familiar with C-like languages such as C, C++, Java, Javascript, etc. things should be quite familiar.

To assist the user, the contents of the reference manual are available to the user in interactive mode as online help. To get help, simply type:

help

or even more briefly,

?

to see the list of main topics. To find help on a particular topic, for example for loops, simply type the topic name afterwards:

? for

Once you're done using morpho, simply type

quit

to exit the program and return to the shell.

The interactive environment has a few other useful features to assist the user:

• Autocomplete. As you type, morpho will show you any suggested commands that it thinks you're trying to enter. For example, if you type v the command line will show the var keyword. To accept the suggestion, press the tab key. Multiple suggestions may be available; use the up and down arrow keys to rotate through them.

• Command history. Use the arrow keys to retrieve previously entered commands. You may then edit them before running them.

• Line editing. As you're typing a command, use the left and right arrows to move the cursor around; you can insert new characters at the cursor just by typing them or delete characters with the delete key. Hold down the shift key as you use the left and right arrow keys to select text; you can then use Ctrl-C to copy and Ctrl-V to paste. Ctrl-A moves to the start of the line and Ctrl-E the end.