Document features

Cargo.toml

@@ -21,7 +21,9 @@ travis-ci = { repository = "crossbeam-rs/crossbeam" }
 
 [features]
 default = ["std"]
-nightly = ["crossbeam-epoch/nightly", "crossbeam-utils/nightly", "crossbeam-queue/nightly"]
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = [
   "alloc",
   "crossbeam-channel/std",
@@ -30,8 +32,17 @@ std = [
   "crossbeam-queue/std",
   "crossbeam-utils/std",
 ]
+
+# Enable to use APIs that require `alloc`.
+# This is enabled by default and also enabled if the `std` feature is enabled.
 alloc = ["crossbeam-epoch/alloc", "crossbeam-queue/alloc"]
 
+# Enable to use of unstable functionality.
+# This is disabled by default and requires recent nightly compiler.
+# Note that this is outside of the normal semver guarantees and minor versions
+# of crossbeam may make breaking changes to them at any time.
+nightly = ["crossbeam-epoch/nightly", "crossbeam-utils/nightly", "crossbeam-queue/nightly"]
+
 [dependencies]
 cfg-if = "0.1.2"
 

crossbeam-channel/Cargo.toml

@@ -17,6 +17,9 @@ categories = ["algorithms", "concurrency", "data-structures"]
 
 [features]
 default = ["std"]
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = ["crossbeam-utils/std"]
 
 [dependencies]

crossbeam-deque/Cargo.toml

@@ -17,6 +17,9 @@ categories = ["algorithms", "concurrency", "data-structures"]
 
 [features]
 default = ["std"]
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = ["crossbeam-epoch/std", "crossbeam-utils/std"]
 
 [dependencies]

crossbeam-epoch/Cargo.toml

@@ -17,9 +17,22 @@ categories = ["concurrency", "memory-management", "no-std"]
 
 [features]
 default = ["std"]
-nightly = ["crossbeam-utils/nightly"]
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = ["alloc", "crossbeam-utils/std", "lazy_static"]
+
+# Enable to use APIs that require `alloc`.
+# This is enabled by default and also enabled if the `std` feature is enabled.
 alloc = []
+
+# Enable to use of unstable functionality.
+# This is disabled by default and requires recent nightly compiler.
+# Note that this is outside of the normal semver guarantees and minor versions
+# of crossbeam may make breaking changes to them at any time.
+nightly = ["crossbeam-utils/nightly"]
+
+# TODO: docs
 sanitize = [] # Makes it more likely to trigger any potential data races.
 
 [dependencies]

crossbeam-queue/Cargo.toml

@@ -17,8 +17,19 @@ categories = ["concurrency", "data-structures"]
 
 [features]
 default = ["std"]
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = ["alloc", "crossbeam-utils/std"]
+
+# Enable to use APIs that require `alloc`.
+# This is enabled by default and also enabled if the `std` feature is enabled.
 alloc = []
+
+# Enable to use of unstable functionality.
+# This is disabled by default and requires recent nightly compiler.
+# Note that this is outside of the normal semver guarantees and minor versions
+# of crossbeam may make breaking changes to them at any time.
 nightly = []
 
 [dependencies]

crossbeam-skiplist/Cargo.toml

@@ -17,10 +17,21 @@ categories = ["algorithms", "concurrency", "data-structures", "no-std"]
 
 [features]
 default = ["std"]
-nightly = ["crossbeam-epoch/nightly", "crossbeam-utils/nightly"]
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = ["alloc", "crossbeam-epoch/std", "crossbeam-utils/std"]
+
+# Enable to use APIs that require `alloc`.
+# This is enabled by default and also enabled if the `std` feature is enabled.
 alloc = ["crossbeam-epoch/alloc"]
 
+# Enable to use of unstable functionality.
+# This is disabled by default and requires recent nightly compiler.
+# Note that this is outside of the normal semver guarantees and minor versions
+# of crossbeam may make breaking changes to them at any time.
+nightly = ["crossbeam-epoch/nightly", "crossbeam-utils/nightly"]
+
 [dependencies]
 cfg-if = "0.1.2"
 

crossbeam-utils/Cargo.toml

@@ -17,9 +17,17 @@ categories = ["algorithms", "concurrency", "data-structures", "no-std"]
 
 [features]
 default = ["std"]
-nightly = []
+
+# Enable to use APIs that require `std`.
+# This is enabled by default.
 std = ["lazy_static"]
 
+# Enable to use of unstable functionality.
+# This is disabled by default and requires recent nightly compiler.
+# Note that this is outside of the normal semver guarantees and minor versions
+# of crossbeam may make breaking changes to them at any time.
+nightly = []
+
 [dependencies]
 cfg-if = "0.1.2"
 lazy_static = { version = "1.1.0", optional = true }