**Exercise to create a tool to improve the concatenation of strings.**
npm install ns-string-builderjs
`$3
js
npm install --save ns-string-builder
`$3
js
var StringBuilder = require('ns-string-builder');
var sb = new StringBuilder();
var paragraphs = ["Why won't the ineffective paradox cruise? A medicine screams next to a class! The lord fulfills the chairman."];
sb
.cat('')
.cat(
'',
['', 'Demo String Builder', ' '],
''
)
.cat('')
.wrap('', '
')
.cat('Hello World!!')
.end()
.wrap('', '
')
.each(paragraphs, function(paragraphs) {
this.cat(paragraphs)
})
.end()
.cat('')
.cat(''); sb.string();
`
cat(value1[, value2 [,valueN]])
Method to add values to the buffer of the StringBuilder.
- Syntax
js
var sb = stringBuilder();
sb.cat('hello');
sb.cat('Javascript', 'crazy', 'world').cat('!!!');
sb.cat(['nestedValue1', 'nestedValue2']).cat(() => 'Hello my Function');
`- Parameters
* values
* Could be strings, arrays and functions.
string()
This method returns a concatenated string of all the parameters that are in the buffer.- Syntax
js
var sb = stringBuilder();
sb.cat('hello', '!!');
sb.string(); // 'hello!!'
`
rep(args1[, argN] ,howManyTimes)
Method that concatenates the same string a given number of times.
- Syntax
js
var sb = new StringBuilder();
sb.cat('Can I go,')
.rep('please ', 2)
.rep('?',3)
`- Parameters
* args
* string values
* howManyTimes
* number of times to repeat string
catIf(args1[,argsN], flag)
Method that performs string concatenation only if the flag is true.
- Syntax
js
sb.cat('Hello')
.catIf('EveryOne', myMood === 'happy');
`- Parameters
* args
* string values
* flag
* boolean value
wrap(prefix, suffix)
Everything added to StringBuilder after this method is called shall be be surrounded by prefix and suffix arguments.
- Syntax
js
sb.cat('', '\n')
.wrap('- ', ['
' ,'\n'])
.rep('list item', 2)
.end()
.cat('
'); // \n- list item
\n- list item
\n
`- Parameters
* prefix
* strings, functions, arrays
* suffix
* strings, functions, arrays
end()
Cancel the current or last effect that was added to the StringBuilder by calling any of the folloowing methods: wrap.prefix(args)
Everything added after calling this method shall be prefix with the specified arguments.
- Syntax
js
sb.prefix('##')
.cat('YEI')
.cat(['!'])
.string(); // "##YEI##!";
`- Parameters
* args
* strings, functions, arrays
suffix(args)
Everything added after calling this method shall be suffix with the specified arguments.
- Syntax
js
sb.suffix('\n')
.cat('Hello')
.cat(['World'])
.string(); // Hello\nWrold\n
`- Parameters
* args
* strings, functions, arrays
each(collection, callback)
Allows the iteration over an array of values without breaking the cascasde or chain.
It shall to iterate over each value on the array and then call the callback function.
The each method will call the callback setting the context(_this_) reference to the
StringBuilder and will send 3 three parameters _value_ , _index_ and _args_ .
- Syntax
js
sb.each(people, function(value, index, people) {
this
.cat('')
.prefix('\t')
.cat('' + value.name + ' ')
.cat('' + value.age + ' ')
.end()
.cat(' ')
});
`- Parameters
* collection
* array
* callback
* function
* with parameters value, index and people
suspend()
This method suspend or pause the applied effects(prefix, suffix and wrap)
and it's influence will finish with the call to end() method.when(expression, thenArgs, otherwiseArgs)
This method evaluate the expression and call the _cat_() method with
the _thenArgs_ or _otherwiseArgs_ depending on the result of evaluation- Syntax
js
sb.suffix('\n')
.wrap('', '
')
.each(fixtures.peopleWithGender, function(person) {
this.when(person.sex == 'm', () => { return person.name + ' is male' }, [ person.name,' is female' ]);
}); sb.string() //
pedro is male
\nleticia is female
\npablo is male
\n;
``- Parameters
* expresion
* function or expressin
* thenArgs
* string, array, function
* otherwiseArgs
* string, array, function