766 lines
23 KiB
Nim
766 lines
23 KiB
Nim
# SPDX-FileCopyrightText: 2021 ☭ Emery Hemingway
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# SPDX-License-Identifier: Unlicense
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import bigints
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import std/[base64, endians, hashes, options, sets, sequtils, streams, tables, typetraits]
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from std/json import escapeJson, escapeJsonUnquoted
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from std/macros import hasCustomPragma, getCustomPragmaVal
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type
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PreserveKind* = enum
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pkBoolean, pkFloat, pkDouble, pkSignedInteger, pkBigInteger, pkString, pkByteString, pkSymbol,
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pkRecord, pkSequence, pkSet, pkDictionary
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const
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atomKinds* = {pkBoolean, pkFloat, pkDouble, pkSignedInteger, pkBigInteger, pkString, pkByteString, pkSymbol}
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compoundKinds* = {pkRecord, pkSequence, pkSet, pkDictionary}
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type
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DictEntry = tuple[key: Preserve, val: Preserve]
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Preserve* {.acyclic.} = object
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case kind*: PreserveKind
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of pkBoolean:
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bool*: bool
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of pkFloat:
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float*: float32
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of pkDouble:
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double*: float64
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of pkSignedInteger:
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int*: BiggestInt
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of pkBigInteger:
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bigint*: BigInt
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of pkString:
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string*: string
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of pkByteString:
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bytes*: seq[byte]
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of pkSymbol:
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symbol*: string
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of pkRecord:
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record*: seq[Preserve] # label is last
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of pkSequence:
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sequence*: seq[Preserve]
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of pkSet:
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set*: seq[Preserve]
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# TODO: HashSet
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of pkDictionary:
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dict*: seq[DictEntry]
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# TODO: Tables
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embedded*: bool
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proc `==`*(x, y: Preserve): bool =
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## Check `x` and `y` for equivalence.
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if x.kind == y.kind and x.embedded == y.embedded:
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case x.kind
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of pkBoolean:
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result = x.bool == y.bool
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of pkFloat:
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result = x.float == y.float
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of pkDouble:
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result = x.double == y.double
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of pkSignedInteger:
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result = x.int == y.int
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of pkBigInteger:
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result = x.bigint == y.bigint
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of pkString:
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result = x.string == y.string
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of pkByteString:
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result = x.bytes == y.bytes
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of pkSymbol:
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result = x.symbol == y.symbol
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of pkRecord:
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result = x.record == y.record
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of pkSequence:
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for i, val in x.sequence:
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if y.sequence[i] != val: return false
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result = true
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of pkSet:
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result = x.set == y.set
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of pkDictionary:
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result = x.dict == y.dict
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proc `<`(x, y: string | seq[byte]): bool =
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for i in 0 .. min(x.high, y.high):
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if x[i] < y[i]: return true
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if x[i] != y[i]: return false
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x.len < y.len
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proc `<`*(x, y: Preserve): bool =
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## Preserves have a total order over Values. Check if `x` is ordered before `y`.
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if x.embedded != y.embedded:
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result = y.embedded
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elif x.kind != y.kind:
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if x.kind == pkSignedInteger and y.kind == pkBigInteger:
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result = x.int.initBigInt < y.bigint
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elif x.kind == pkBigInteger and y.kind == pkSignedInteger:
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result = x.bigint < y.int.initBigInt
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else:
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result = x.kind < y.kind
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else:
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case x.kind
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of pkBoolean:
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result = (not x.bool) and y.bool
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of pkFloat:
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result = x.float < y.float
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of pkDouble:
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result = x.double < y.double
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of pkSignedInteger:
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result = x.int < y.int
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of pkBigInteger:
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result = x.bigint < y.bigint
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of pkString:
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result = x.string < y.string
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of pkByteString:
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result = x.bytes < y.bytes
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of pkSymbol:
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result = x.symbol < y.symbol
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of pkRecord:
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if x.record[x.record.high] < y.record[y.record.high]: return true
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for i in 0..<min(x.record.high, y.record.high):
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if x.record[i] < y.record[i]: return true
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if x.record[i] == y.record[i]: return false
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result = x.record.len < y.record.len
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of pkSequence:
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for i in 0..min(x.sequence.high, y.sequence.high):
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if x.sequence[i] < y.sequence[i]: return true
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if x.sequence[i] != y.sequence[i]: return false
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result = x.sequence.len < y.sequence.len
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of pkSet:
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for i in 0..min(x.set.high, y.set.high):
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if x.set[i] < y.set[i]: return true
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if x.set[i] != y.set[i]: return false
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result = x.set.len < y.set.len
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of pkDictionary:
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for i in 0..min(x.dict.high, y.dict.high):
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if x.dict[i].key < y.dict[i].key: return true
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if x.dict[i].key == y.dict[i].key:
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if x.dict[i].val < y.dict[i].val: return true
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if x.dict[i].val != y.dict[i].val: return false
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result = x.dict.len < y.dict.len
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proc hash*(pr: Preserve): Hash =
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## Produce a `Hash` of `pr` for use with a `HashSet` or `Table`.
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var h = hash(pr.kind.int) !& hash(pr.embedded)
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case pr.kind
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of pkBoolean:
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h = h !& hash(pr.bool)
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of pkFloat:
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h = h !& hash(pr.float)
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of pkDouble:
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h = h !& hash(pr.double)
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of pkSignedInteger:
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h = h !& hash(pr.int)
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of pkBigInteger:
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h = h !& hash(pr.bigint.flags)
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h = h !& hash(pr.bigint)
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of pkString:
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h = h !& hash(pr.string)
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of pkByteString:
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h = h !& hash(pr.bytes)
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of pkSymbol:
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h = h !& hash(pr.symbol)
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of pkRecord:
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for val in pr.record:
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h = h !& hash(val)
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of pkSequence:
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for val in pr.sequence:
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h = h !& hash(val)
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of pkSet:
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for val in pr.set.items:
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h = h !& hash(val)
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of pkDictionary:
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for (key, val) in pr.dict.items:
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h = h !& hash(key) !& hash(val)
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!$h
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proc `[]`*(pr: Preserve; i: int): Preserve =
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## Select an indexed value from `pr`.
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## Only valid for records and sequences.
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case pr.kind
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of pkRecord: pr.record[i]
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of pkSequence: pr.sequence[i]
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else:
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raise newException(ValueError, "`[]` is not valid for " & $pr.kind)
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proc incl*(pr: var Preserve; key: Preserve) =
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## Include `key` in the Preserves set `pr`.
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for i in 0..pr.set.high:
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if key < pr.set[i]:
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insert(pr.set, [key], i)
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return
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pr.set.add(key)
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proc excl*(pr: var Preserve; key: Preserve) =
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## Exclude `key` from the Preserves set `pr`.
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for i in 0..pr.set.high:
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if pr.set[i] == key:
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delete(pr.set, i, i)
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break
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proc `[]`*(pr: var Preserve; key: Preserve): Preserve =
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## Select a value by `key` from the Preserves dictionary `pr`.
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for (k, v) in pr.dict.items:
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if k == key: return v
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raise newException(KeyError, "value not in Preserves dictionary")
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proc `[]=`*(pr: var Preserve; key, val: Preserve) =
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## Insert `val` by `key` in the Preserves dictionary `pr`.
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for i in 0..pr.dict.high:
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if key < pr.dict[i].key:
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insert(pr.dict, [(key, val, )], i)
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return
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elif key == pr.dict[i].key:
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pr.dict[i].val = val
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return
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pr.dict.add((key, val, ))
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proc symbol*(s: string; E = void): Preserve {.inline.} =
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## Create a Preserves symbol value.
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Preserve(kind: pkSymbol, symbol: s)
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proc initRecord*(label: Preserve; args: varargs[Preserve]): Preserve =
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## Create a Preserves record value.
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result = Preserve(kind: pkRecord,
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record: newSeqOfCap[Preserve](1+args.len))
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for arg in args:
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result.record.add(arg)
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result.record.add(label)
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proc initRecord*(label: string; args: varargs[Preserve, toPreserve]): Preserve =
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## Convert ``label`` to a symbol and create a new record.
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runnableExamples:
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assert($initRecord("foo", 1, 2.0) == "<foo 1 2.0f>")
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initRecord(symbol(label), args)
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proc initSet*(): Preserve = Preserve(kind: pkSet)
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## Create a Preserves set value.
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proc initDictionary*(): Preserve = Preserve(kind: pkDictionary)
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## Create a Preserves dictionary value.
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proc len*(pr: Preserve): int =
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## Return the shallow count of values in ``pr``, that is the number of
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## fields in a record, items in a sequence, items in a set, or key-value pairs
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## in a dictionary.
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case pr.kind
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of pkRecord: pr.record.len.pred
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of pkSequence: pr.sequence.len
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of pkSet: pr.set.len
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of pkDictionary: pr.dict.len
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else: 0
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iterator items*(pr: Preserve): Preserve =
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## Shallow iterator over `pr`, yield the fields in a record,
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## the items of a sequence, the items of a set, or the pairs
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## of a dictionary.
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case pr.kind
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of pkRecord:
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for i in 0..pr.record.high.pred:
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yield pr.record[i]
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of pkSequence:
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for e in pr.sequence.items: yield e
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of pkSet:
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for e in pr.set.items: yield e
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of pkDictionary:
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for (k, v) in pr.dict.items:
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yield k # key can be an arbitrary Preserve
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yield v
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else: discard
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proc isFalse*(pr: Preserve): bool =
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## Check if ``pr`` is equivalent to the zero-initialized ``Preserve``.
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pr.kind == pkBoolean and pr.bool == false
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proc isSymbol*(pr: Preserve; sym: string): bool =
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## Check if `pr` is a Preserves symbol.
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(pr.kind == pkSymbol) and (pr.symbol == sym)
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proc isRecord*(pr: Preserve): bool =
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## Check if `pr` is a Preserves record.
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if pr.kind == pkRecord:
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result = true
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assert(pr.record.len > 0)
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proc isDictionary*(pr: Preserve): bool =
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## Check if `pr` is a Preserves dictionary.
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pr.kind == pkDictionary
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proc label*(pr: Preserve): Preserve {.inline.} =
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## Return the label of record value.
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pr.record[pr.record.high]
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proc arity*(pr: Preserve): int {.inline.} =
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## Return the number of fields in record `pr`.
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pred(pr.record.len)
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proc fields*(pr: Preserve): seq[Preserve] {.inline.} =
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## Return the fields of a record value.
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pr.record[0..pr.record.high.pred]
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iterator fields*(pr: Preserve): Preserve =
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## Iterate the fields of a record value.
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for i in 0..<pr.record.high: yield pr.record[i]
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proc writeVarint(s: Stream; n: int) =
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var n = n
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while true:
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let c = int8(n and 0x7f)
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n = n shr 7
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if n == 0:
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s.write((char)c.char)
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break
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else:
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s.write((char)c or 0x80)
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proc readVarint(s: Stream): int =
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var shift: int
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while shift < (9*8):
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let c = s.readChar.int
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result = result or ((c and 0x7f) shl shift)
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if (c and 0x80) == 0:
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break
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shift.inc 7
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proc write*(str: Stream; pr: Preserve) =
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## Write the binary-encoding of a Preserves value to a stream.
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if pr.embedded: str.write(0x86'u8)
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case pr.kind:
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of pkBoolean:
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case pr.bool
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of false: str.write(0x80'u8)
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of true: str.write(0x81'u8)
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of pkFloat:
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str.write(0x82'u8)
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when system.cpuEndian == bigEndian:
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str.write(pr.float)
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else:
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var be: float32
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swapEndian32(be.addr, pr.float.unsafeAddr)
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str.write(be)
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of pkDouble:
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str.write(0x83'u8)
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when system.cpuEndian == bigEndian:
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str.write(pr.double)
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else:
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var be: float64
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swapEndian64(be.addr, pr.double.unsafeAddr)
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str.write(be)
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of pkSignedInteger:
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if (-3 <= pr.int) and (pr.int <= 12):
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str.write(0x90'i8 or int8(if pr.int < 0: pr.int + 16 else: pr.int))
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else:
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var bitCount = 1'u8
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if pr.int < 0:
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while ((not pr.int) shr bitCount) != 0:
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inc(bitCount)
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else:
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while (pr.int shr bitCount) != 0:
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inc(bitCount)
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var byteCount = (bitCount + 8) div 8
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str.write(0xa0'u8 or (byteCount - 1))
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proc write(n: uint8; i: BiggestInt) =
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if n > 0:
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write(n.pred, i shr 8)
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str.write(i.uint8)
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write(byteCount, pr.int)
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of pkBigInteger:
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doAssert(Negative notin pr.bigint.flags, "negative big integers not implemented")
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var bytes = newSeqOfCap[uint8](pr.bigint.limbs.len * 4)
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var begun = false
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for i in countdown(pr.bigint.limbs.high, 0):
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let limb = pr.bigint.limbs[i]
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for j in countdown(24, 0, 8):
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let b = uint8(limb shr j)
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begun = begun or (b != 0)
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if begun:
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bytes.add(b)
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if bytes.len <= 16:
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str.write(0xa0'u8 or bytes.high.uint8)
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else:
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str.write(0xb0'u8)
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str.writeVarint(bytes.len)
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str.write(cast[string](bytes))
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of pkString:
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str.write(0xb1'u8)
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str.writeVarint(pr.string.len)
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str.write(pr.string)
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of pkByteString:
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str.write(0xb2'u8)
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str.writeVarint(pr.bytes.len)
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str.write(cast[string](pr.bytes))
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of pkSymbol:
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str.write(0xb3'u8)
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str.writeVarint(pr.symbol.len)
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str.write(pr.symbol)
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of pkRecord:
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assert(pr.record.len > 0)
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str.write(0xb4'u8)
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str.write(pr.record[pr.record.high])
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for i in 0..<pr.record.high:
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str.write(pr.record[i])
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str.write(0x84'u8)
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of pkSequence:
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str.write(0xb5'u8)
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for e in pr.sequence:
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str.write(e)
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str.write(0x84'u8)
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of pkSet:
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str.write(0xb6'u8)
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for val in pr.set.items:
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str.write(val)
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str.write(0x84'u8)
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of pkDictionary:
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str.write(0xb7'u8)
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for (key, value) in pr.dict.items:
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str.write(key)
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str.write(value)
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str.write(0x84'u8)
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proc encode*(pr: Preserve): seq[byte] =
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## Return the binary-encoding of a Preserves value.
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let s = newStringStream()
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s.write pr
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s.setPosition 0
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result = cast[seq[byte]](s.readAll)
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proc decodePreserves*(s: Stream): Preserve =
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## Decode a Preserves value from a binary-encoded stream.
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proc assertStream(check: bool) =
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if not check:
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raise newException(ValueError, "invalid Preserves stream")
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const endMarker = 0x84
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let tag = s.readUint8()
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case tag
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of 0x80: result = Preserve(kind: pkBoolean, bool: false)
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of 0x81: result = Preserve(kind: pkBoolean, bool: true)
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of 0x82:
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when system.cpuEndian == bigEndian:
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result = Preserve(kind: pkFloat, float: s.readFloat32())
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else:
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result = Preserve(kind: pkFloat)
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var be = s.readFloat32()
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swapEndian32(result.float.addr, be.addr)
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of 0x83:
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when system.cpuEndian == bigEndian:
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result = Preserve(kind: pkDouble, double: s.readFloat64())
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else:
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result = Preserve(kind: pkDouble)
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var be = s.readFloat64()
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swapEndian64(result.double.addr, be.addr)
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of 0x86:
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result = decodePreserves(s)
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result.embedded = true
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of 0xb1:
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result = Preserve(kind: pkString)
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let len = s.readVarint()
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result.string = s.readStr(len)
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of 0xb2:
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result = Preserve(kind: pkByteString)
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let len = s.readVarint()
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result.bytes = cast[seq[byte]](s.readStr(len))
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of 0xb3:
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let len = s.readVarint()
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result = Preserve(kind: pkSymbol, symbol: s.readStr(len))
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of 0xb4:
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result = Preserve(kind: pkRecord)
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var label = decodePreserves(s)
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while s.peekUint8() != endMarker:
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result.record.add decodePreserves(s)
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result.record.add(move label)
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discard s.readUint8()
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of 0xb5:
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result = Preserve(kind: pkSequence)
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while s.peekUint8() != endMarker:
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result.sequence.add decodePreserves(s)
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discard s.readUint8()
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of 0xb6:
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result = Preserve(kind: pkSet)
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while s.peekUint8() != endMarker:
|
|
incl(result, decodePreserves(s))
|
|
discard s.readUint8()
|
|
of 0xb7:
|
|
result = Preserve(kind: pkDictionary)
|
|
while s.peekUint8() != endMarker:
|
|
result[decodePreserves(s)] = decodePreserves(s)
|
|
discard s.readUint8()
|
|
of 0xb0:
|
|
let len = s.readVarint()
|
|
result = Preserve(kind: pkBigInteger, bigint: initBigint 0)
|
|
for _ in 1..len:
|
|
result.bigint = (result.bigint shl 8) + s.readUint8().int32
|
|
of endMarker:
|
|
assertStream(false)
|
|
else:
|
|
case 0xf0 and tag
|
|
of 0x90:
|
|
var n = tag.BiggestInt
|
|
result = Preserve(kind: pkSignedInteger,
|
|
int: n - (if n > 0x9c: 0xa0 else: 0x90))
|
|
of 0xa0:
|
|
let len = (tag.int and 0x0f) + 1
|
|
if len <= 8:
|
|
result = Preserve(kind: pkSignedInteger, int: s.readUint8().BiggestInt)
|
|
if (result.int and 0x80) != 0: result.int.dec(0x100)
|
|
for i in 1..<len:
|
|
result.int = (result.int shl 8) or s.readUint8().BiggestInt
|
|
else:
|
|
result = Preserve(kind: pkBigInteger)
|
|
for i in 0..<len:
|
|
result.bigint = (result.bigint shl 8) + s.readUint8().int32
|
|
else:
|
|
assertStream(false)
|
|
|
|
proc decodePreserves*(s: string): Preserve =
|
|
## Decode a string of binary-encoded Preserves.
|
|
s.newStringStream.decodePreserves
|
|
|
|
proc decodePreserves*(s: seq[byte]): Preserve =
|
|
## Decode a byte-string of binary-encoded Preserves.
|
|
cast[string](s).decodePreserves
|
|
|
|
template record*(label: string) {.pragma.}
|
|
## Serialize this object or tuple as a record. See ``toPreserve``.
|
|
|
|
template unpreservable*() {.pragma.}
|
|
## Pragma to forbid a type from being converted by ``toPreserve``.
|
|
|
|
proc toPreserve*[T](x: T): Preserve =
|
|
## Serializes ``x`` to Preserves. Can be customized by defining
|
|
## ``toPreserveHook(x: T)`` in the calling scope.
|
|
when (T is Preserve): result = x
|
|
elif compiles(toPreserveHook(x)):
|
|
result = toPreserveHook(x)
|
|
elif T is Bigint:
|
|
result = Preserve(kind: pkBigInteger, bigint: x)
|
|
elif T is seq[byte]:
|
|
result = Preserve(kind: pkByteString, bytes: x)
|
|
elif T is array | seq:
|
|
result = Preserve(kind: pkSequence)
|
|
for v in x.items: result.sequence.add(toPreserve(v))
|
|
elif T is bool:
|
|
result = Preserve(kind: pkBoolean, bool: x)
|
|
elif T is distinct:
|
|
result = toPreserve(x.distinctBase)
|
|
elif T is float:
|
|
result = Preserve(kind: pkFloat, float: x)
|
|
elif T is float64:
|
|
result = Preserve(kind: pkDouble, double: x)
|
|
elif T is object | tuple:
|
|
when T.hasCustomPragma(unpreservable): {.fatal: "unpreservable type".}
|
|
elif T.hasCustomPragma(record):
|
|
result = Preserve(kind: pkRecord)
|
|
for _, f in x.fieldPairs: result.record.add(toPreserve(f))
|
|
result.record.add(symbol(T.getCustomPragmaVal(record)))
|
|
else:
|
|
result = Preserve(kind: pkDictionary)
|
|
for k, v in x.fieldPairs:
|
|
result[symbol(k)] = toPreserve(v)
|
|
elif T is Ordinal:
|
|
result = Preserve(kind: pkSignedInteger, int: x.ord.BiggestInt)
|
|
elif T is ptr | ref:
|
|
if system.`==`(x, nil): result = symbol("null")
|
|
else: result = toPreserve(x[])
|
|
elif T is string:
|
|
result = Preserve(kind: pkString, string: x)
|
|
elif T is SomeInteger:
|
|
result = Preserve(kind: pkSignedInteger, int: x.BiggestInt)
|
|
else:
|
|
raiseAssert("unpreservable type" & $T)
|
|
|
|
proc toPreserveHook*[T](set: HashSet[T]): Preserve =
|
|
## Hook for preserving ``HashSet``.
|
|
Preserve(kind: pkSet, set: set.map(toPreserve))
|
|
|
|
proc toPreserveHook*[A, B](table: Table[A, B]|TableRef[A, B]): Preserve =
|
|
## Hook for preserving ``Table``.
|
|
result = Preserve(kind: pkDictionary, dict: initTable[Preserve, Preserve](table.len))
|
|
for k, v in table.pairs: result.dict.add((k.toPreserve, v.toPreserve, ))
|
|
|
|
proc fromPreserve*[T](v: var T; pr: Preserve): bool =
|
|
## Inplace version of `preserveTo`. Returns ``true`` on
|
|
## a complete match, otherwise returns ``false``.
|
|
# TODO: {.raises: [].}
|
|
runnableExamples:
|
|
import preserves, preserves/parse
|
|
type Foo {.record: "foo".} = object
|
|
x, y: int
|
|
var foo: Foo
|
|
assert(fromPreserve(foo, parsePreserves("""<foo 1 2>""")))
|
|
assert(foo.x == 1)
|
|
assert(foo.y == 2)
|
|
type Value = Preserve
|
|
when T is Value:
|
|
v = pr
|
|
result = true
|
|
elif compiles(fromPreserveHook(v, pr)):
|
|
result = fromPreserveHook(v, pr)
|
|
elif T is Bigint:
|
|
case pr.kind
|
|
of pkSignedInteger:
|
|
v = initBigint(pr.int)
|
|
result = true
|
|
of pkBigInteger:
|
|
v = pr.bigint
|
|
result = true
|
|
else: disard
|
|
elif T is bool:
|
|
if pr.kind == pkBoolean:
|
|
v = pr.bool
|
|
result = true
|
|
elif T is SomeInteger:
|
|
if pr.kind == pkSignedInteger:
|
|
v = T(pr.int)
|
|
result = true
|
|
elif T is float:
|
|
if pr.kind == pkFloat:
|
|
v = pr.float
|
|
result = true
|
|
elif T is seq:
|
|
if T is seq[byte] and pr.kind == pkByteString:
|
|
v = pr.bytes
|
|
result = true
|
|
elif pr.kind == pkSequence:
|
|
v.setLen(pr.len)
|
|
result = true
|
|
for i, e in pr.sequence:
|
|
result = result and fromPreserve(v[i], e)
|
|
elif T is float64:
|
|
case pr.kind
|
|
of pkFloat:
|
|
v = pr.float
|
|
result = true
|
|
of pkDouble:
|
|
v = pr.double
|
|
result = true
|
|
elif T is object | tuple:
|
|
case pr.kind
|
|
of pkRecord:
|
|
when T.hasCustomPragma(record):
|
|
if pr.record[pr.record.high].isSymbol T.getCustomPragmaVal(record):
|
|
result = true
|
|
var i = 0
|
|
for fname, field in v.fieldPairs:
|
|
if not result or (i == pr.record.high): break
|
|
result = result and fromPreserve(field, pr.record[i])
|
|
inc(i)
|
|
result = result and (i == pr.record.high) # arity equivalence check=
|
|
of pkDictionary:
|
|
result = true
|
|
var fieldCount = 0
|
|
for key, val in v.fieldPairs:
|
|
inc fieldCount
|
|
for (pk, pv) in pr.dict.items:
|
|
var sym = symbol(key)
|
|
if sym == pk:
|
|
result = result and fromPreserve(val, pv)
|
|
break
|
|
result = result and pr.dict.len == fieldCount
|
|
else: discard
|
|
elif T is Ordinal | SomeInteger:
|
|
if pr.kind == pkSignedInteger:
|
|
v = (T)pr.int
|
|
result = true
|
|
elif T is ref:
|
|
if pr != symbol("null"):
|
|
new v
|
|
result = fromPreserve(v[], pr)
|
|
elif T is string:
|
|
if pr.kind == pkString:
|
|
v = pr.string
|
|
result = true
|
|
elif T is distinct:
|
|
result = fromPreserve(result.distinctBase, pr)
|
|
else:
|
|
raiseAssert("no conversion of type Preserve to " & $T)
|
|
if not result: reset v
|
|
|
|
proc preserveTo*(pr: Preserve; T: typedesc): Option[T] =
|
|
## Reverse of `toPreserve`.
|
|
##
|
|
# TODO: {.raises: [].}
|
|
runnableExamples:
|
|
import std/options, preserves, preserves/parse
|
|
type Foo {.record: "foo".} = object
|
|
x, y: int
|
|
|
|
assert(parsePreserves("""<foo "abc">""").preserveTo(Foo).isNone)
|
|
assert(parsePreserves("""<bar 1 2>""").preserveTo(Foo).isNone)
|
|
assert(parsePreserves("""<foo 1 2>""").preserveTo(Foo).isSome)
|
|
var v: T
|
|
if fromPreserve(v, pr):
|
|
result = some(move v)
|
|
|
|
proc fromPreserveHook*[A,B,E](t: var Table[A,B]|TableRef[A,B]; pr: Preserve): bool =
|
|
if pr.isDictionary:
|
|
for k, v in pr.pairs:
|
|
t[preserveTo(k, A)] = preserveTo(v, B)
|
|
result = true
|
|
|
|
proc concat(result: var string; pr: Preserve) =
|
|
if pr.embedded: result.add("#!")
|
|
case pr.kind:
|
|
of pkBoolean:
|
|
case pr.bool
|
|
of false: result.add "#f"
|
|
of true: result.add "#t"
|
|
of pkFloat:
|
|
result.add($pr.float & "f")
|
|
of pkDouble:
|
|
result.add $pr.double
|
|
of pkSignedInteger:
|
|
result.add $pr.int
|
|
of pkBigInteger:
|
|
result.add $pr.bigint
|
|
of pkString:
|
|
result.add escapeJson(pr.string)
|
|
of pkByteString:
|
|
for b in pr.bytes:
|
|
if b.char notin {'\20'..'\21', '#'..'[', ']'..'~'}:
|
|
result.add("#[") #]#
|
|
result.add(base64.encode(pr.bytes))
|
|
result.add(']')
|
|
return
|
|
result.add("#\"")
|
|
result.add(cast[string](pr.bytes))
|
|
result.add('"')
|
|
of pkSymbol:
|
|
result.add(escapeJsonUnquoted(pr.symbol))
|
|
of pkRecord:
|
|
assert(pr.record.len > 0)
|
|
result.add('<')
|
|
result.concat(pr.record[pr.record.high])
|
|
for i in 0..<pr.record.high:
|
|
result.add(' ')
|
|
result.concat(pr.record[i])
|
|
result.add('>')
|
|
of pkSequence:
|
|
result.add('[')
|
|
for i, val in pr.sequence:
|
|
if i > 0:
|
|
result.add(' ')
|
|
result.concat(val)
|
|
result.add(']')
|
|
of pkSet:
|
|
result.add("#{")
|
|
for val in pr.set.items:
|
|
result.concat(val)
|
|
result.add(' ')
|
|
if pr.set.len > 1:
|
|
result.setLen(result.high)
|
|
result.add('}')
|
|
of pkDictionary:
|
|
result.add('{')
|
|
var i = 0
|
|
for (key, value) in pr.dict.items:
|
|
if i > 0:
|
|
result.add(' ')
|
|
result.concat(key)
|
|
result.add(": ")
|
|
result.concat(value)
|
|
inc i
|
|
result.add('}')
|
|
|
|
proc `$`*(pr: Preserve): string = concat(result, pr)
|
|
## Generate the textual representation of ``pr``.
|