A cheat sheet for nim
Built in:
char: 'c' '\l'
int8: 1_024'i8
int16: 0xbeef'i16
int32: 0o71'i32
int64: 0b10'i64
float32: 1_000.5e-10'f64
float64: 1_000.5e-10'f64
string: "a\"b", r"a""b", """a"b"""
# with \n: new line (platform dependant)
# \l: LF (10) \r: CR (13)
# var s: string = newString(4)type
TDirection = enum
north, east, south, west
TSubrange = range[0..5]
TDollar = distinct int
TEuro = distinct int
type
TIntArray = array[0..5, int] # an array that is indexed with 0..5
TIntSeq = seq[int]
x = [1, 2, 3, 4, 5, 6] # [] is the array constructor
low(x) -> high(x)
y = @[1, 2, 3, 4, 5, 6] # the @ turns the array into a sequence
0 -> len(y) - 1, init with proc newSeq*[T](s: var seq[T], len: int)
type TPerson = tuple[name: string, age: int]
var person : TPerson = (name: "Peter", age: 30)
type
TCallback = proc (x: int) {.cdecl.}type
TPerson = object
name*: string # the * means that `name` is accessible from other modules
age: int # no * means that the field is hidden
TStudent = object of TPerson # a student is a person
id: int # with an id field
PNode = ref TNode
TNode = object
case kind: TNodeKind # the ``kind`` field is the discriminator
of nkInt: intVal: int
of nkFloat: floatVal: float
of nkString: strVal: string
of nkAdd, nkSub:
leftOp, rightOp: PNode
of nkIf:
condition, thenPart, elsePart: PNode
`assert(student is TStudent)`{} # emtpy set
{'a'..'z', '0'..'9'} # This constructs a set that contains the
# letters from 'a' to 'z' and the digits
# from '0' to '9'
a + b # union of two sets
a * b # intersection of two sets
a - b # difference of two sets (a without b's elements)
a == b # set equality
a <= b # subset relation (a is subset of b or equal to b)
a < b # strong subset relation (a is a real subset of b)
e in a # set membership (a contains element e)
a -+- b # symmetric set difference (= (a - b) + (b - a))
card(a) # the cardinality of a (number of elements in a)Traced references are declared with the ref keyword, untraced references are declared with the ptr keyword.
The ^ operator can be used to derefer a reference, the addr procedure returns the address of an item.
An address is always an untraced reference.
type
TBinaryTree[T] = object # TBinaryTree is a generic type with
# with generic param ``T``
le, ri: ref TBinaryTree[T] # left and right subtrees; may be nil
data: T # the data stored in a node
PBinaryTree[T] = ref TBinaryTree[T] # a shorthand for notational convenience
proc newNode[T](data: T): PBinaryTree[T] = # constructor for a node
new(result)
result.data = dataproc myWriteln(f: TFile, a: openarray[string]) =
for s in items(a):
write(f, s)
write(f, "\n")
proc callme(x, y: int, s: string = "", c: char, b: bool = false) = ...
callme(0, 1, "abc", '\t', true) # (x=0, y=1, s="abc", c='\t', b=true)
callme(y=1, x=0, "abd", '\t') # (x=0, y=1, s="abd", c='\t', b=false)
callme(c='\t', y=1, x=0) # (x=0, y=1, s="", c='\t', b=false)
callme 0, 1, "abc", '\t'
proc `$` (x: int): string =
return intToStr(x)if name == "Andreas":
echo("What a nice name!")
elif name == "":
echo("Don't you have a name?")
else:
echo("Boring name...")
case readline(stdin)
of "delete-everything", "restart-computer":
echo("permission denied")
of "go-for-a-walk": echo("please yourself")
else: echo("unknown command")
when isMainModule:
when defined(win32):
elif defined(macosx):
else:
var f: TFile
if open(f, "numbers.txt"):
try:
var a = readLine(f)
raise newEOS("operating system failed")
except EIO:
echo("IO error!")
except:
echo("Unknown exception!")
finally:
close(f)
var found = false
block myblock:
for i in 0..3:
for j in 0..3:
if a[j][i] == 7:
found = true
break myblock # leave the block, in this case both for-loops
while pw != "12345":
echo("Wrong password! Next try: \n")
continue
pw = readLine(stdin)
iterator items*(a: string): char {.inline.} =
var i = 0
while i < len(a):
yield a[i]
inc(i)
for ch in items("hello world"): # `ch` is an iteration variable
echo(ch)
ternary: p(if x > 8: 9 else: 10)template declareInNewScope(x: expr, t: typeDesc): stmt =
# open a new scope:
block:
var x: t
declareInScope(a, int)
a = 42 # works, `a` is known hereproc printf(formatstr: cstring) {.importc: "printf", varargs.}
proc callme(formatstr: cstring) {.exportc: "callMe", varargs.}
proc Tcl_Eval(interp: pTcl_Interp, script: cstring): int {.cdecl,
importc, dynlib: "libtcl(|8.5|8.4|8.3).so.(1|0)".}When building a library with --app:lib:
proc exportme(): int {.cdecl, export, dynlib.} compile, c compile project with default code generator (C)
doc generate the documentation for inputfile
i start Nimrod in interactive mode (limited)
compileToC, cc compile project with C code generator
compileToOC, oc compile project to Objective C code
rst2html convert a reStructuredText file to HTML
rst2tex convert a reStructuredText file to TeX
run run the project (with Tiny C backend; buggy!)
pretty pretty print the inputfile
genDepend generate a DOT file containing the
module dependency graph
dump dump all defined conditionals and search paths
check checks the project for syntax and semantic
-p, --path:PATH add path to search paths
-d, --define:SYMBOL define a conditional symbol
-u, --undef:SYMBOL undefine a conditional symbol
-f, --forceBuild force rebuilding of all modules
--stackTrace:on|off turn stack tracing on|off
--lineTrace:on|off turn line tracing on|off
--threads:on|off turn support for multi-threading on|off
-x, --checks:on|off turn all runtime checks on|off
--objChecks:on|off turn obj conversion checks on|off
--fieldChecks:on|off turn case variant field checks on|off
--rangeChecks:on|off turn range checks on|off
--boundChecks:on|off turn bound checks on|off
--overflowChecks:on|off turn int over-/underflow checks on|off
-a, --assertions:on|off turn assertions on|off
--floatChecks:on|off turn all floating point (NaN/Inf) checks on|off
--nanChecks:on|off turn NaN checks on|off
--infChecks:on|off turn Inf checks on|off
--deadCodeElim:on|off whole program dead code elimination on|off
--opt:none|speed|size optimize not at all or for speed|size
--app:console|gui|lib generate a console|GUI application|dynamic library
-r, --run run the compiled program with given arguments
--advanced show advanced command line switches
-h, --help show this help
--track:FILE,LINE,COL track a file/cursor position
--suggest suggest all possible symbols at position
--def list all possible symbols at position
--context list possible invokation context
Compile with --debugger:on, without --app:gui. Commands:
s: step_into n: step_over f: skip_current
c: continue i: ignore
b <identifier> [fromline [toline]] [file] or {.breakpoint: "before_write_2".}
breakpoints: Display the entire breakpoint list.
disable: <identifier> enable: <identifier>
- Compiler / Parser is not built into the core libs
- Interruptible/Resettable iterators
- Examples of OO common cases
- DSLs, moaaard DSLs
Rebuild argument list with:
{:help => [2,4], :advanced => [1,2]}.map { |k, v| `nimrod --#{k}`.split(/^[^\n]*:\n/m).values_at(*v) }.flatten.values_at(0,2,1,3).each_with_index { |v, i| puts [["### Commands ###\n", "", "\n### Arguments ###\n", ""][i],v.rstrip.gsub(/^(?!#)/, " ")].join("") } #.gsub(/^( +)(.*?)( *)$/m, "\\1`\\2`\\3")