Files
markdown-parsing/Sources/main.swift

146 lines
3.0 KiB
Swift

import Foundation
@preconcurrency import Parsing
let yamlString = """
author: Michael Housh
categories:
- HVAC
- General
- Programming
copy: true
draft: false
date: 2023-10-21
lastmod: 2023-10-21
image: banner.png
featuredImage: banner.png
tags:
- HVAC
- General
- Programming
title: "You Should Learn Markdown"
"""
_ = """
series:
- General
title: "You Should Learn Markdown"
slug: "you-should-learn-markdown"
"""
struct SimpleYamlValue: Parser {
enum Output: Equatable {
case array([String])
case bool(Bool)
case date(year: Int, month: Int, day: Int)
case string(String)
}
var body: some Parser<Substring.UTF8View, Output> {
OneOf {
// YamlList().map { Output.array($0) }
DateParser()
Bool.parser().map(.case(Output.bool))
PrefixUpTo("\n".utf8).map(.string).map(.case(Output.string))
Rest().map(.string).map(.case(Output.string))
}
}
struct DateParser: Parser {
var body: some Parser<Substring.UTF8View, Output> {
Parse {
Digits(4)
"-".utf8
Digits(2)
"-".utf8
Digits(2)
}.map(.case(Output.date))
}
}
}
struct SimpleYamlParser: Parser {
typealias Output = [String: SimpleYamlValue.Output]
var body: some Parser<Substring.UTF8View, Output> {
Many(into: Output()) { (dict: inout Output, pair: (String, SimpleYamlValue.Output)) in
let (key, value) = pair
dict[key] = value
} element: {
// Parses a key and array.
OneOf {
Parse {
PrefixUpTo(":".utf8).map(.string)
":\n".utf8
Many(into: [String]()) { array, string in
array.append(string)
} element: {
From(.substring) { Whitespace() }
"-".utf8
From(.substring) { Whitespace() }
PrefixUpTo("\n".utf8).map(.string)
} separator: {
"\n".utf8
}
// terminator: {
// OneOf {
// Peek { PrefixUpTo(":".utf8) }
// End()
// }
// }
}
.map { ($0.0, SimpleYamlValue.Output.array($0.1)) }
// Parse a key and a single value.
Parse {
PrefixUpTo(":".utf8).map(.string)
":".utf8
Whitespace()
SimpleYamlValue()
}
}
} separator: {
"\n".utf8
} terminator: {
End()
}
}
}
let simpleYamlString = #"""
author: Michael Housh
copy: true
draft: false
date: 2023-10-21
lastmod: 2023-10-21
image: banner.png
featuredImage: banner.png
test:
- HVAC
- General
- Programming
foo: Bar
"""#
var keyedList = """
test:
- HVAC
- General
- Programming
foo: Bar
"""[...].utf8
// let parsedList = try keyedListParser.parse(&keyedList)
// print(parsedList)
let parsed = try SimpleYamlParser().parse(simpleYamlString[...].utf8)
// let parsed = try SimpleYamlParser().parse(yamlString[...].utf8)
for (key, value) in parsed {
print("\(key): \(value)")
}
// assert(parsed.keys.count == 10)
// try print(SimpleYamlParser().parse(simpleYamlString[...].utf8))