reference.md

Table of Contents

• Command line arguments
• Flow control
  • Branching
  • Looping
    • Lists
    • Forever
• Functions
• Operators
  • +
    • string
• Packages
• Iterating
• Built-in functions
  • print
  • format
  • len
  • append
  • exit
  • glob
• Standard Library

Here lies a comprehensive reference documentation of nash features and built-in functions, and how to use them.

There is also some examples that can be useful.

Command line arguments

To handle script arguments you can just use the ARGS variable, that is a list populated with the arguments passed to your script when it is executed, like:

echo
echo "acessing individual parameter"
var somearg = $ARGS[0]
echo $somearg
echo

Flow control

Branching

To branch you can use if statement, it requires a boolean expression, like the comparison operator:

var a = "nash"
echo -n $a
if $a == "nash" {
    a = "rocks"
}
echo $a
#Output:"nashrocks"

You can also use a junction of boolean expressions:

a = "nash"
b = "rocks"
if $a == "nash" && $b == "rocks"{
    echo "hellyeah"
}
#Output:"hellyeah"

You can also use a disjunction of boolean expressions:

a = "nash"
b = "rocks"
if $a == "bash" || $b == "rocks"{
    echo "hellyeah"
}
#Output:"hellyeah"

Looping

Right now there are two kind of loops, on lists and the forever kind :-).

Lists

You can iterate lists like this:

a = ""
for i in ("nash" "rocks"){
    a = $a + $i
}
echo $a
#Output:"nashrocks"

Forever

It would be cool to loop on boolean expressions, but right now we can only loop forever (besides list looping):

for {
    echo "hi"
}

Functions

Defining functions is very easy, for example:

fn concat(a, b) {
        return $a+$b
}

res <= concat("1","9")
echo $res

#Output:"19"

If a parameter is missing on the function call, it will fail:

fn concat(a, b) {
        return $a, $b
}

res <= concat("1")
echo $res

#Output:"ERROR: Wrong number of arguments for function concat. Expected 2 but found 1"

Passing extra parameters will also fail:

fn concat(a, b) {
        return $a, $b
}

res <= concat("1","2","3")
echo $res

#Output:"ERROR: Wrong number of arguments for function concat. Expected 2 but found 3"

Operators

+

The + operator behaviour is dependent on the type its operands. It is always invalid to mix types on the operation (like one operand is a string and the other one is a integer).

The language is dynamically typed, but it is strongly typed, types can't be mixed on operations, there is no implicit type coercion.

string

String concatenation is pretty straightforward. For example:

a = "1"
b = "2"

echo $a+$b
#Output:"12"

Packages

TODO

Iterating

TODO

Built-in functions

Built-in functions are functions that are embedded on the language. You do not have to import any package to use them.

print

The function print is used to print simple messages directly to stdout:

print("hi")
#Output:"hi"

And supports formatting:

print("%s:%s", "1", "2")
#Output:"1:2"

format

The function format is used like print, but instead of writing to stdout it will return the string according to the format provided:

a <= format("%s:%s", "1", "2")
echo $a
#Output:"1:2"

len

The function len returns the length of a list. An example to check for the length of a list:

echo "define one list with two elements"
args = (
    "one"
    "two"
)
echo "getting list length"
argslen <= len($args)
echo $argslen

append

The function append appends one element to the end of a exist list. Append returns the updated list.

An example to append one element to a exist list:

example_list = ()
echo "appending string 1"
example_list <= append($example_list, "1")
echo $example_list
echo "appending string 2"
example_list <= append($example_list, "2")
echo $example_list

exit

TODO

glob

TODO

Standard Library

The standard library is a set of packages that comes with the nash install (although not obligatory).

They must be imported explicitly (as any other package) to be used.

• fmt