summaryrefslogtreecommitdiff
path: root/src/engine/SCons/Subst.xml
blob: bc2daa3007ad829968bd03979fe4ad9cbe1bd8ab (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
<!--
Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 The SCons Foundation

This file is processed by the bin/SConsDoc.py module.
See its __doc__ string for a discussion of the format.
-->

<scons_function name="AllowSubstExceptions">
<arguments signature="global">
([exception, ...])
</arguments>
<summary>
Specifies the exceptions that will be allowed
when expanding construction variables.
By default,
any construction variable expansions that generate a
<literal>NameError</literal>
or
<literal>IndexError</literal>
exception will expand to a
<literal>''</literal>
(a null string) and not cause scons to fail.
All exceptions not in the specified list
will generate an error message
and terminate processing.

If
&f-AllowSubstExceptions;
is called multiple times,
each call completely overwrites the previous list
of allowed exceptions.

Example:

<example>
# Requires that all construction variable names exist.
# (You may wish to do this if you want to enforce strictly
# that all construction variables must be defined before use.)
AllowSubstExceptions()

# Also allow a string containing a zero-division expansion
# like '${1 / 0}' to evalute to ''.
AllowSubstExceptions(IndexError, NameError, ZeroDivisionError)
</example>
</summary>
</scons_function>