In the next few chapters, you will learn about Vimscript, Vim's built-in programming language.
When learning a new language, there are three basic elements to look for:
- Primitives
- Means of Combination
- Means of Abstraction
This chapter will cover the first part, Vim's primitive data types.
In this chapter, you will learn Vim's primitive data types.
## Data Types
Vim has 10 different data types:
- Number
- Float
- String
@ -25,7 +23,7 @@ Vim has 10 different data types:
- Channel
- Blob
In this chapter, you will learn the first six types. In Ch. 27, you will learn about Funcref. For more about Vim data types, check out `:h variables`.
I will cover the first six data types here. In Ch. 27, you will learn about Funcref. For more about Vim data types, check out `:h variables`.
## Echo
@ -51,7 +49,7 @@ For the remaining of the chapter, I will use `:echo` (because it is one letter s
## Number
Vim has 4 different number types: decimal, hexadecimal, binary, and octal.
Vim has 4 different number types: decimal, hexadecimal, binary, and octal. By the way, when I say number data type, often this means an integer data type. In this guide, I will use the terms number and integer interchangeably.
### Decimal
@ -71,7 +69,7 @@ Octals start with `0`, `0o`, and `0O`. Mnemonic: **O**ctal.
### Printing Numbers
If you `echo` either a hexadecimal, binary, or octal number, Vim automatically converts them to decimals.
If you `echo` either a hexadecimal, a binary, or an octal number, Vim automatically converts them to decimals.
```viml
:echo 42
@ -89,7 +87,7 @@ If you `echo` either a hexadecimal, binary, or octal number, Vim automatically c
### Truthy and Falsy
In Vim, 0 is falsy and all non-0 values are truthy.
In Vim, a 0 value is falsy and all non-0 values are truthy.
The following will not echo anything.
@ -107,7 +105,7 @@ However, this will:
:endif
```
Any values other than 0 will be truthy, including negative numbers. 100 is truthy. -1 is truthy.
Any values other than 0 is truthy, including negative numbers. 100 is truthy. -1 is truthy.
### Number Arithmetic
@ -154,7 +152,7 @@ Floats are numbers with trailing decimals. There are two ways to represent float
" returns 0.25
```
You need to give a float a dot and trailing digits. `25e-2` (no dot) and `1234.` (no trailing digits) are both invalid float numbers.
You need to give a float a dot and trailing digits. `25e-2` (no dot) and `1234.` (has a dot, but no trailing digits) are both invalid float numbers.
### Float Arithmetic
@ -187,14 +185,14 @@ To concatenate a string in Vim, use the `.` operator.
### String Arithmetic
When you run arithmetic operators (`+ - * /`) against a string, Vim coerces the string into a number.
When you run arithmetic operators (`+ - * /`) with a number and a string, Vim coerces the string into a number.
```viml
:echo "12 donuts" + 3
" returns 15
```
When Vim sees "12 donuts", it extracts the 12 from the string and converts it into the number 12. Then it performs addition, returning 15. For this string-to-number coercion to work, the number character needs to be the *first character* in the string.
When Vim sees "12 donuts", it extracts the 12 from the string and converts it into the number 12. Then it performs addition, returning 15. For this string-to-number coercion to work, the number character needs to be the *first character* in the string.
The following won't work because 12 is not the first character in the string:
@ -210,7 +208,7 @@ This also won't work because an empty space is the first character of the string
" returns 3
```
This coercion works even with multiple strings:
This coercion works even with two strings:
```
:echo "12 donuts" + "6 pastries"
@ -240,7 +238,7 @@ A neat trick to force a string-to-number conversion is to just add 0 or multiply
" returns 12
```
When arithmetic is done against a float number, Vim only looks at the number part.
When arithmetic is done against a float in a string, Vim treats it like an integer, not a float:
```
:echo "12.0 donuts" + 12
@ -273,6 +271,7 @@ In the following if statement, Vim coerces "12donuts" into 12, which is truthy:
:if "12donuts"
: echo "Yum"
:endif
" returns "Yum"
```
On the other hand, this is falsy:
@ -281,13 +280,14 @@ On the other hand, this is falsy:
:if "donuts12"
: echo "Nope"
:endif
" rerturns nothing
```
Vim coerces "donuts12" into 0, because the first character of the String is not a number.
Vim coerces "donuts12" into 0, because the first character is not a number.
### Double vs Single quotes
Double quotes behave differently than single quotes. Single quotes display characters literally. Double quotes accepts special characters.
Double quotes behave differently than single quotes. Single quotes display characters literally while double quotes accept special characters.
What are special characters? Check out the newline and double-quotes display:
@ -368,7 +368,7 @@ There are many other string procedures. Check out `:h string-functions`.
## List
A Vimscript list is like an Array in Javascript, Python, or Ruby. It is an *ordered* sequence of items. You can mix-and-match the content with different data types:
A Vimscript list is like an Array in Javascript or List in Python. It is an *ordered* sequence of items. You can mix-and-match the content with different data types:
```
[1,2,3]
@ -377,9 +377,9 @@ A Vimscript list is like an Array in Javascript, Python, or Ruby. It is an *orde
[1,2,[3,4]]
```
### Accessing List elements (sublists)
### Sublists
Vim's list is zero-indexed. You can access a particular item in a list with `[n]`, where n is the index.
Vim list is zero-indexed. You can access a particular item in a list with `[n]`, where n is the index.
```
:echo ["a", "sweet", "dessert"][0]
@ -433,9 +433,9 @@ You can pass an index that exceeds the maximum items when slicing an array.
Many list targetting and slicing techniques above can be applied to string:
You can slice and target strings just like lists:
```viml
:echo "choco"[0]
@ -462,7 +462,7 @@ You can use `+` to concatenate and mutate a list:
" returns ["chocolate", "strawberry", "sugar"]
```
### List functions
### List Functions
Let's explore Vim's built-in list functions.
@ -521,7 +521,7 @@ The `v:val` variable is a Vim special variable. It is available when iterating a
For more, check out `:h list-functions`.
### List unpacking
### List Unpacking
You can unpack a list and assign variables to the list items:
@ -599,10 +599,10 @@ If you are too lazy to put quotes around each key, you can use the `#{}` notatio
The only requirement for using the `#{}` syntax is that each key must be either:
- ASCII character
- digit
- `_`
- `-`
- ASCII character.
- Digit.
- An underscore (`_`).
- A hyphen (`-`).
Just like list, you can use any data type as values.
@ -734,7 +734,7 @@ By the way, `v:` is Vim's built-in variable. They will be covered more in Ch 26.
In my experience, you won't use these special primitives often. If you need a truthy / falsy value, you can just use 0 (falsy) and non-0 (truthy). If you need an empty string, just use `""`. But it is still good to know, so let's quickly go over them.
### `v:true`
### True
This is equivalent to `true`. It is equivalent to a number with value of non-0 . When decoding json with `json_encode()`, it is interpreted as "true".
@ -743,7 +743,7 @@ This is equivalent to `true`. It is equivalent to a number with value of non-0 .
" returns {"test": true}
```
### `v:false`
### False
This is equivalent to `false`. It is equivalent to a number with value of 0. When decoding json with `json_encode()`, it is interpreted as "false".
@ -752,7 +752,7 @@ This is equivalent to `false`. It is equivalent to a number with value of 0. Whe
" returns {"test": false}
```
### `v:none`
### None
It is equivalent to an empty string. When decoding json with `json_encode()`, it is interpreted as an empty item (`null`).
@ -761,7 +761,7 @@ It is equivalent to an empty string. When decoding json with `json_encode()`, it
Igor Irianto
3 years ago