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-rw-r--r--docs/units-and-global-variables.rst78
1 files changed, 39 insertions, 39 deletions
diff --git a/docs/units-and-global-variables.rst b/docs/units-and-global-variables.rst
index 8fa515cc..8f910c80 100644
--- a/docs/units-and-global-variables.rst
+++ b/docs/units-and-global-variables.rst
@@ -7,23 +7,23 @@ Units and Globally Available Variables
Ether Units
===========
-A literal number can take a suffix of :code:`wei`, :code:`finney`, :code:`szabo` or :code:`ether` to convert between the subdenominations of Ether, where Ether currency numbers without a postfix are assumed to be "wei", e.g. :code:`2 ether == 2000 finney` evaluates to :code:`true`.
+A literal number can take a suffix of ``wei``, ``finney``, ``szabo`` or ``ether`` to convert between the subdenominations of Ether, where Ether currency numbers without a postfix are assumed to be "wei", e.g. ``2 ether == 2000 finney`` evaluates to ``true``.
.. index:: time, seconds, minutes, hours, days, weeks, years
Time Units
==========
-Suffixes of :code:`seconds`, :code:`minutes`, :code:`hours`, :code:`days`, :code:`weeks` and
+Suffixes of ``seconds``, ``minutes``, ``hours``, ``days``, ``weeks`` and
`years` after literal numbers can be used to convert between units of time where seconds are the base
unit and units are considered naively in the following way:
- * :code:`1 == 1 second`
- * :code:`1 minutes == 60 seconds`
- * :code:`1 hours == 60 minutes`
- * :code:`1 days == 24 hours`
- * :code:`1 weeks = 7 days`
- * :code:`1 years = 365 days`
+ * ``1 == 1 second``
+ * ``1 minutes == 60 seconds``
+ * ``1 hours == 60 minutes``
+ * ``1 days == 24 hours``
+ * ``1 weeks = 7 days``
+ * ``1 years = 365 days``
Take care if you perform calendar calculations using these units, because
not every year equals 365 days and not even every day has 24 hours
@@ -50,29 +50,29 @@ namespace and are mainly used to provide information about the blockchain.
Block and Transaction Properties
------------------------------------
- - :code:`block.coinbase` (:code:`address`): current block miner's address
- - :code:`block.difficulty` (:code:`uint`): current block difficulty
- - :code:`block.gaslimit` (:code:`uint`): current block gaslimit
- - :code:`block.number` (:code:`uint`): current block number
- - :code:`block.blockhash` (:code:`function(uint) returns (bytes32)`): hash of the given block - only for 256 most recent blocks
- - :code:`block.timestamp` (:code:`uint`): current block timestamp
- - :code:`msg.data` (:code:`bytes`): complete calldata
- - :code:`msg.gas` (:code:`uint`): remaining gas
- - :code:`msg.sender` (:code:`address`): sender of the message (current call)
- - :code:`msg.sig` (:code:`bytes4`): first four bytes of the calldata (i.e. function identifier)
- - :code:`msg.value` (:code:`uint`): number of wei sent with the message
- - :code:`now` (:code:`uint`): current block timestamp (alias for :code:`block.timestamp`)
- - :code:`tx.gasprice` (:code:`uint`): gas price of the transaction
- - :code:`tx.origin` (:code:`address`): sender of the transaction (full call chain)
+ - ``block.coinbase`` (``address``): current block miner's address
+ - ``block.difficulty`` (``uint``): current block difficulty
+ - ``block.gaslimit`` (``uint``): current block gaslimit
+ - ``block.number`` (``uint``): current block number
+ - ``block.blockhash`` (``function(uint) returns (bytes32)``): hash of the given block - only for 256 most recent blocks
+ - ``block.timestamp`` (``uint``): current block timestamp
+ - ``msg.data`` (``bytes``): complete calldata
+ - ``msg.gas`` (``uint``): remaining gas
+ - ``msg.sender`` (``address``): sender of the message (current call)
+ - ``msg.sig`` (``bytes4``): first four bytes of the calldata (i.e. function identifier)
+ - ``msg.value`` (``uint``): number of wei sent with the message
+ - ``now`` (``uint``): current block timestamp (alias for ``block.timestamp``)
+ - ``tx.gasprice`` (``uint``): gas price of the transaction
+ - ``tx.origin`` (``address``): sender of the transaction (full call chain)
.. note::
- The values of all members of :code:`msg`, including :code:`msg.sender` and
- :code:`msg.value` can change for every **external** function call.
+ The values of all members of ``msg``, including ``msg.sender`` and
+ ``msg.value`` can change for every **external** function call.
This includes calls to library functions.
If you want to implement access restrictions in library functions using
- :code:`msg.sender`, you have to manually supply the value of
- :code:`msg.sender` as an argument.
+ ``msg.sender``, you have to manually supply the value of
+ ``msg.sender`` as an argument.
.. note::
The block hashes are not available for all blocks for scalability reasons.
@@ -84,17 +84,17 @@ Block and Transaction Properties
Mathematical and Cryptographic Functions
----------------------------------------
-:code:`addmod(uint x, uint y, uint k) returns (uint)`:
- compute :code:`(x + y) % k` where the addition is performed with arbitrary precision and does not wrap around at :code:`2**256`.
-:code:`mulmod(uint x, uint y, uint k) returns (uint)`:
- compute :code:`(x * y) % k` where the multiplication is performed with arbitrary precision and does not wrap around at :code:`2**256`.
-:code:`sha3(...) returns (bytes32)`:
+``addmod(uint x, uint y, uint k) returns (uint)``:
+ compute ``(x + y) % k`` where the addition is performed with arbitrary precision and does not wrap around at ``2**256``.
+``mulmod(uint x, uint y, uint k) returns (uint)``:
+ compute ``(x * y) % k`` where the multiplication is performed with arbitrary precision and does not wrap around at ``2**256``.
+``sha3(...) returns (bytes32)``:
compute the Ethereum-SHA-3 hash of the (tightly packed) arguments
-:code:`sha256(...) returns (bytes32)`:
+``sha256(...) returns (bytes32)``:
compute the SHA-256 hash of the (tightly packed) arguments
-:code:`ripemd160(...) returns (bytes20)`:
+``ripemd160(...) returns (bytes20)``:
compute RIPEMD-160 hash of the (tightly packed) arguments
-:code:`ecrecover(bytes32 data, uint8 v, bytes32 r, bytes32 s) returns (address)`:
+``ecrecover(bytes32 data, uint8 v, bytes32 r, bytes32 s) returns (address)``:
recover the address associated with the public key from elliptic curve signature
In the above, "tightly packed" means that the arguments are concatenated without padding.
@@ -106,20 +106,20 @@ This means that the following are all identical::
sha3(6382179)
sha3(97, 98, 99)
-If padding is needed, explicit type conversions can be used: :code:`sha3("\x00\x12")` is the
-same as :code:`sha3(uint16(0x12))`.
+If padding is needed, explicit type conversions can be used: ``sha3("\x00\x12")`` is the
+same as ``sha3(uint16(0x12))``.
-It might be that you run into Out-of-Gas for :code:`sha256`, :code:`ripemd160` or :code:`ecrecover` on a *private blockchain*. The reason for this is that those are implemented as so-called precompiled contracts and these contracts only really exist after they received the first message (although their contract code is hardcoded). Messages to non-existing contracts are more expensive and thus the execution runs into an Out-of-Gas error. A workaround for this problem is to first send e.g. 1 Wei to each of the contracts before you use them in your actual contracts. This is not an issue on the official or test net.
+It might be that you run into Out-of-Gas for ``sha256``, ``ripemd160`` or ``ecrecover`` on a *private blockchain*. The reason for this is that those are implemented as so-called precompiled contracts and these contracts only really exist after they received the first message (although their contract code is hardcoded). Messages to non-existing contracts are more expensive and thus the execution runs into an Out-of-Gas error. A workaround for this problem is to first send e.g. 1 Wei to each of the contracts before you use them in your actual contracts. This is not an issue on the official or test net.
.. index:: this, selfdestruct
Contract Related
----------------
-:code:`this` (current contract's type):
+``this`` (current contract's type):
the current contract, explicitly convertible to :ref:`address`
-:code:`selfdestruct(address)`:
+``selfdestruct(address)``:
destroy the current contract, sending its funds to the given :ref:`address`
Furthermore, all functions of the current contract are callable directly including the current function.