parse

Parses typeof(null) from a character range if the range spells "null". This function is case insensitive.

auto parse(Source source)
auto parse(Source s)
auto parse(Source source, uint radix)
auto parse(Source s)
auto parse(Source source)
auto parse(Source s)
auto parse(Source s)
auto parse(Source s)
auto
parse
(
Target
Source
Flag!"doCount" doCount = No.doCount
)
(
ref Source s
)
if (
is(immutable Target == immutable typeof(null)) &&
isInputRange!Source
&&
isSomeChar!(ElementType!Source)
)
auto parse(Source s, dchar lbracket, dchar rbracket, dchar comma)
auto parse(Source s, dchar lbracket, dchar rbracket, dchar comma)
auto parse(Source s, dchar lbracket, dchar rbracket, dchar keyval, dchar comma)

Parameters

Target: the type to convert to
s Source: the lvalue of an input range
doCount: the flag for deciding to report the number of consumed characters

Return Value

Type: auto

null if doCount is set to No.doCount
A tuple containing null and a size_t if doCount is set to Yes.doCount

Throws

A ConvException if the range doesn't represent null.

Examples

import std.exception : assertThrown;
import std.typecons : Flag, Yes, No;

alias NullType = typeof(null);
auto s1 = "null";
assert(parse!NullType(s1) is null);
assert(s1 == "");

auto s2 = "NUll"d;
assert(parse!NullType(s2) is null);
assert(s2 == "");

auto s3 = "nuLlNULl";
assert(parse!(NullType, string, No.doCount)(s3) is null);
auto r = parse!(NullType, string, Yes.doCount)(s3);
assert(r.data is null && r.count == 4);

auto m = "maybe";
assertThrown!ConvException(parse!NullType(m));
assertThrown!ConvException(parse!(NullType, string, Yes.doCount)(m));
assert(m == "maybe");  // m shouldn't change on failure

auto s = "NULL";
assert(parse!(const NullType)(s) is null);

parse

Parameters

Return Value

Throws

Examples

Meta

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