Command Syntax
All commands in the program are words that consist of a primary word (a noun/object) and a first keyword (a verb/action). To this foundation may be added options and modifiers (adverb(s)). Lastly, the entirety of the command may be filtered through a range (a prepositional phrase). In other words, commands syntactically mimic natural language.
The latter components (options, modifiers, and ranges) are not uniformly required by all commands; they are frequently optional. These parts also usually require user-supplied values to be completed.
The syntactical pattern is expressed as
NOUN - VERB - OPTION(S) - MODIFIER(S) - RANGE
Note the order is consistent and required in all commands. That said, parts may be omitted in the middle when optional. Thus commands may manifest the simpler pattern NOUN - VERB - RANGE when OPTION and MODIFIER components are optional (which is most commands).
Syntax Pattern Examples
NOUN-VERB
program quit
model new
This is the simplest of command patterns. In these lines, program
and model
are the NOUN component; quit
and new
are the VERB component. The first command exits the program. The second command clears the current model state. See program quit
and model new
for reference information on these commands.
NOUN-VERB-OPTION, with and without RANGE
NOUN-VERB-MODIFIER, with and without RANGE
NOUN-VERB-OPTION-MODIFIER, with and without RANGE
To recap, a command will always have, at minimum, a NOUN and a VERB. Depending on the command, these two may be followed by:
zero, one, or more OPTIONs
zero, one, or more MODIFIERs (which will vary the effect of the command), and
zero or one (and one only) RANGE phrase (which will restrict the effect of the command).
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