99 lines
3.2 KiB
Markdown
99 lines
3.2 KiB
Markdown
Value Conversions
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=================
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{{#include ../links.md}}
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Convert Between Integer and Floating-Point
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------------------------------------------
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| Function | Not available under | From type | To type |
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| ------------ | :-----------------: | :---------------------------------------: | :-----------------------: |
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| `to_int` | | `INT`, `FLOAT`, [`Decimal`][rust_decimal] | `INT` |
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| `to_float` | [`no_float`] | `INT`, `FLOAT`, [`Decimal`][rust_decimal] | `FLOAT` |
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| `to_decimal` | non-[`decimal`] | `INT`, `FLOAT`, [`Decimal`][rust_decimal] | [`Decimal`][rust_decimal] |
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That's it; for other conversions, register custom conversion functions.
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```js
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let x = 42; // 'x' is an integer
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let y = x * 100.0; // integer and floating-point can inter-operate
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let y = x.to_float() * 100.0; // convert integer to floating-point with 'to_float'
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let z = y.to_int() + x; // convert floating-point to integer with 'to_int'
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let d = y.to_decimal(); // convert floating-point to Decimal with 'to_decimal'
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let w = z.to_decimal() + x; // Decimal and integer can inter-operate
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let c = 'X'; // character
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print(`c is '${c}' and its code is ${c.to_int()}`); // prints "c is 'X' and its code is 88"
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```
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Parse String into Number
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------------------------
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| Function | From type | To type |
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| ---------------------------------------- | :-------: | :-----------------------: |
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| `parse_int` | [string] | `INT` |
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| `parse_int` with radix 2-36 | [string] | `INT` (specified radix) |
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| `parse_float` (not [`no_float`]) | [string] | `FLOAT` |
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| `parse_float` ([`no_float`]+[`decimal`]) | [string] | [`Decimal`][rust_decimal] |
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| `parse_decimal` (requires [`decimal`]) | [string] | [`Decimal`][rust_decimal] |
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```rust
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let x = parse_float("123.4"); // parse as floating-point
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x == 123.4;
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type_of(x) == "f64";
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let x = parse_decimal("123.4"); // parse as Decimal value
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type_of(x) == "decimal";
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let x = 1234.to_decimal() / 10; // alternate method to create a Decimal value
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type_of(x) == "decimal";
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let dec = parse_int("42"); // parse as integer
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dec == 42;
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type_of(dec) == "i64";
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let dec = parse_int("42", 10); // radix = 10 is the default
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dec == 42;
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type_of(dec) == "i64";
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let bin = parse_int("110", 2); // parse as binary (radix = 2)
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bin == 0b110;
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type_of(bin) == "i64";
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let hex = parse_int("ab", 16); // parse as hex (radix = 16)
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hex == 0xab;
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type_of(hex) == "i64";
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```
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Format Numbers
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--------------
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| Function | From type | To type | Format |
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| ----------- | :-------: | :------: | :----------------------------: |
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| `to_binary` | `INT` | [string] | binary (i.e. only `1` and `0`) |
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| `to_octal` | `INT` | [string] | octal (i.e. `0` ... `7`) |
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| `to_hex` | `INT` | [string] | hex (i.e. `0` ... `f`) |
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```rust
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let x = 0x1234abcd;
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x == 305441741;
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x.to_string() == "305441741";
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x.to_binary() == "10010001101001010101111001101";
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x.to_octal() == "2215125715";
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x.to_hex() == "1234abcd";
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```
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