v/builtin/smap.v

102 lines
1.6 KiB
Go

// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
module builtin
struct Entry2 {
key string
val string
}
struct smap {
entries []Entry2
is_sorted bool
}
fn new_smap() smap {
res := smap{}
return res
}
fn (m mut smap) set(key string, val string) {
/*
for i := 0; i < m.entries.len; i++ {
entry := m.entries[i]
if entry.key == key {
e := Entry2{key: key, val: val}
m.entries[i] = e
return
}
}
*/
e := Entry2{key: key, val: val}
m.entries << e
}
fn (m smap) get(key string) string {
if m.is_sorted {
return m.bs(key, 0, m.entries.len)
}
for i := 0; i < m.entries.len; i++ {
entry := m.entries[i]
if entry.key == key {
return entry.val
}
}
return ''
}
fn (m smap) bs(query string, start, end int) string {
mid := start + ((end - start) / 2)
if end - start == 0 {
last := m.entries[end]
return last.val
}
if end - start == 1 {
first := m.entries[start]
return first.val
}
if mid >= m.entries.len {
return ''
}
mid_msg := m.entries[mid]
if query < mid_msg.key {
return m.bs(query, start, mid)
}
return m.bs(query, mid, end)
}
fn compare_smap(a, b *Entry2) int {
if a.key < b.key {
return -1
}
if a.key > b.key {
return 1
}
return 0
}
fn (m mut smap) sort() {
m.entries.sort_with_compare(compare_smap)
m.is_sorted = true
}
fn (m smap) free() {
// m.entries.free()
}
fn (m smap) str() string {
if m.entries.len == 0 {
return '{}'
}
// TODO use bytes buffer
mut s := '{\n'
for entry in m.entries {
s += ' "$entry.key" => "$entry.val"\n'
}
s += '}'
return s
}