3.1.
GENESIS Statements and Commands
GENESIS routines are called by entering a routine name followed by any
necessary arguments and options separated by whitespace.
routine-name arg1 arg2 ... -option1 option1-arg1 ... -option2 ...
A valid routine-name is a script identifier consisting of any
combination of alphabetic (A-Z or a-z) or numeric (0-9) characters, or
underscores (``_'') -- all other symbols are invalid characters in an
identifier.
Routine arguments consist of literal strings of characters, results of
other GENESIS routines or expressions, strings of characters including
whitespace enclosed in double quotes and the value of parameters
passed to a script or function. Combinations of these which appear
together without any intervening whitespace are concatenated and
passed as a single argument to the routine.
Routine options follow command arguments, and are introduced by a dash
character. Option names may be abbreviated to any unambiguous length.
Each option may accept additional arguments following the option name.
A carriage return marks the end of a statement, so you do not need to
use semicolons at the end of a line. However, you can use semicolons
to terminate statements as a way to include multiple statements on a
single line. Several examples:
genesis > reset; step 100
genesis > int a, b, c ; a=1 ; b=2 ; c=3
genesis > if( a < b); echo {a} is less than {b}; end
1 is less than 2
In other cases, the ``command'' returns a value and might more properly be called a function. In the documentation for GENESIS commands,
we will use the term ``routine'' for built-in GENESIS commands, and
will reserve the term ``function'' for a script function that is written in the GENESIS scripting language. The procedure for creating
your own functions is described under ``Functions'' (Functions.doc).
The following two examples illustrate how a routine call can be
supplied as the argument to another routine or as a value in a script
language expression:
genesis > echo { getfield /neutral_test x }
genesis > float length = { getfield /cell/soma len }
Routines used in the context of an argument to another routine or
within a script language expression must be enclosed in curly
brackets.
All GENESIS statements are subject to these and other basic
syntactical rules. If a statement you submit violates these rules,
the interpreter will respond with an error message (and ignore your
instruction).