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preserves
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The cheatsheet is better as a single block

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Tony Garnock-Jones 2022-06-11 10:16:24 +02:00
parent 9668bcbb03
commit 6e0592256d
1 changed files with 10 additions and 18 deletions
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cheatsheet.md
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@ -10,8 +10,6 @@ June 2022. Version 0.7.0.
For a value `v`, we write `«v»` for the binary encoding of `v`.
### Atoms
«#f» = [0xA0]
«#t» = [0xA1]
«F» = [0xA2] ++ binary32(F) if F ∈ Float
@ -21,16 +19,6 @@ For a value `v`, we write `«v»` for the binary encoding of `v`.
[0xA5] ++ S if S ∈ ByteString
[0xA6] ++ utf8(S) if S ∈ Symbol
The functions `binary32(F)` and `binary64(D)` yield big-endian 4- and
8-byte IEEE 754 binary representations of `F` and `D`, respectively.
The function `intbytes(x)` gives the big-endian two's-complement signed
binary representation of `x`, taking exactly as many whole bytes as
needed to unambiguously identify the value and its sign. `intbytes(0)`
is the empty byte sequence.
### Compounds
«<L F_1...F_m>» = [0xA7] ++ seq(«L», «F_1», ..., «F_m»)
«[X_1...X_m]» = [0xA8] ++ seq(«X_1», ..., «X_m»)
«#{E_1...E_m}» = [0xA9] ++ seq(«E_1», ..., «E_m»)
@ -43,14 +31,18 @@ is the empty byte sequence.
e(v, d) = [v + d] if v < 128
e(v / 128, 0) ++ [(v % 128) + d] if v ≥ 128
### Embeddeds
«#!V» = [0xBF] ++ «V»
### Annotations
The functions `binary32(F)` and `binary64(D)` yield big-endian 4- and
8-byte IEEE 754 binary representations of `F` and `D`, respectively.
To annotate a `Repr` `r` (that *MUST NOT* itself already be annotated)
with some sequence of `Value`s `[v_1, ..., v_m]`, surround `r` as
follows:
The function `intbytes(x)` gives the big-endian two's-complement signed
binary representation of `x`, taking exactly as many whole bytes as
needed to unambiguously identify the value and its sign. `intbytes(0)`
is the empty byte sequence.
**Annotations.** To annotate a `Repr` `r` (that *MUST NOT* itself
already be annotated) with some sequence of `Value`s `[v_1, ..., v_m]`,
surround `r` as follows:
[0xBE] ++ len(|r|) ++ r ++ len(|«v_1»|) ++ «v_1» ++...++ len(|«v_m»|) ++ «v_m»