Configuring Prefix and Suffix Rules

There are several rules that enforce specific prefixes or suffixes in different name identifiers. It is noted in the documentation, what the default prefixes and suffixes are for each such rule.

All prefix and suffix rules are disabled by default. The defaults for each of these rules can be overridden using a configuration.

Note

Some elements have both prefix and suffix rules. Depending on the desired style, either or both can be enabled.

Overriding Default Prefix Enforcement

The default setting can be changed using a configuration. The rule variable_012 defaults to following prefix: [‘v_’]. We can use the following configuration to change allowed prefix:

rule :
    variable_012:
        # Each prefix rule needs to be enabled explicitly.
        disable: false
        prefixes: ['var_']

Overriding Default Suffix Enforcement

The default setting can be changed using a configuration. For example, the rule port_025 defaults to following suffixes: [‘_I’, ‘_O’, ‘_IO’]. We can use the following configuration to change allowed suffixes:

rule :
    port_025:
        # Each suffix rule needs to be enabled explicitly.
        disable: false
        suffixes: ['_i', '_o']

Exceptions to Prefix and Suffix Enforcement

Exceptions to enforcing prefixes and suffixes can be given using the exceptions option:

rule :
    port_025:
        # Each suffix rule needs to be enabled explicitly.
        disable: false
        suffixes: ['_i', '_o']
        exceptions: ['CLK', '.*_FIELD']

The exceptions option provides a list of keywords, that when matched, prevents the rule from validating the prefix or suffix. The keywords are treated as case insensitive and support regular expressions.

Rules Enforcing Prefixes and Suffixes

Element	Prefix Rule	Suffix Rule
Block Label	block_601	block_600
Constant Identifier	constant_015	constant_600
Function Designator	function_600	function_601
Generate Label	generate_017	generate_600
Generate Parameter Identifier	generate_601	generate_602
Generic Identifier	generic_020	generic_600
Generic Map Identifier	generic_map_601	generic_map_600
Loop Label	loop_600	loop_601
Loop Parameter Identifier	loop_602	loop_603
Package Identifier	package_017	package_016
Package Body Identifier	package_body_601	package_body_600
Port Identifier	port_011	port_025
Process Label	process_036	process_600
Signal Identifier	signal_008	signal_600
Subtype Identifier	subtype_004	subtype_600
Type Identifier	type_definition_015	type_definition_600
Variable Identifier	variable_012	variable_600