Map

Map represents a language map file. Usually, it is a text file that contains key-value pairs separated by a equal sign. The key is the name of the language feature. The built-in keys are:

ext: the file extension for the language
comment: the line comment pattern for the language
int: the integer type for the language
int8: the 8-bit integer type for the language
int16: the 16-bit integer type for the language
int32: the 32-bit integer type for the language
int64: the 64-bit integer type for the language
float32: the 32-bit floating-point type for the language
float64: the 64-bit floating-point type for the language
bool: the boolean type for the language
string: the string type for the language
byte: the byte type for the language
bytes: the byte slice type for the language
any: the any type for the language
array: the fixed-sized array type for the language
vector: the slice type for the language
map: the map type for the language
box: the box replacement for the language (for java, e.g., box(int) = Integer)

Here are some examples of language map files:

java.map
cpp.map
protobuf.map

java.map
ext=.java
comment=// %T%

# primitive types

int=int
int8=byte
int16=short
int32=int
int64=long
float32=float
float64=double
bool=boolean
string=String
byte=byte
bytes=byte[]
any=Object
map=Map<box(%K%),box(%V%)>
vector=List<box(%T%)>
array=%T%[]

# box types

box(int)=Integer
box(byte)=Byte
box(short)=Short
box(long)=Long
box(float)=Float
box(double)=Double
box(boolean)=Boolean

cpp.map
ext=.h
comment=// %T%

int=int
int8=int8_t
int16=int16_t
int32=int32_t
int64=int64_t
float32=float
float64=double
bool=bool
string=std::string
byte=unsigned char
bytes=std::vector<unsigned char>
any=std::any
map=std::unordered_map<%K%, %V%>
vector=std::vector<%T%>
array=std::array<%T%, %N%>

protobuf.map
ext=.proto
comment=// %T%

int=int32
int8=int32
int16=int32
int32=int32
int64=int64
float32=float
float64=double
bool=bool
string=string
byte=int8
bytes=bytes
any=google.protobuf.Any
map=map<%K%, %V%>
vector=repeated %T.E%
array=repeated %T.E%

tip

The %T%, %K%, %V% and %N% are placeholders for the type, key type, value type and number of array elements.
%T.E% is the final element type of %T%. It's useful if you need to get the final element type of a vector or array.
Line comments are started with the # character and it must be the first character of the line (leading spaces are allowed).

java.map
ext=.java # This is an invalid comment
# Comment must be the first character of the line

	# This is a valid comment (leading spaces are allowed)

See Builtin Map Files for more information.